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BMW E30 3 Series Differential Oil Change

In this continuing series of maintenance article for the BMW E30 3 Series models, we will focus on changing the differential oil. This article is written with the 325is model in mind, however this article applies to all BMW’s in general.

Why change the differential oil? The differential is just like any other mechanism with moving parts. It generates heat and friction while in operation. Just like an engine, regular oil changes help to keep parts such as gears well lubricated and clean. Over time, the differential wears just like any other component. The differences between the differential and an engine is that the differential has no internal filter to capture small particles of metal as the gears wear. Also, the differential uses oil that is much thicker than engine oil. Usually differential oil is good for up to 80,000 miles without changing. However it is commonly overlooked in the wide spectrum of vehicle maintenance. Failure to change the fluid at regular intervals can cause a variety of problems, eventually causing the bearings in the diff to fail. In this article I will go over the simple steps to changing the oil yourself and avoid a costly trip to your mechanic for something you can do in under an hour in your driveway.

First, drive the car around the block a few times to get the oil inside the differential warmed up,

Now, let’s jack the car up. First, chock the front wheels to keep them from rolling while you have the rear wheels jacked up. Be sure to jack the car up on a re-inforced part of the body, such as a crossmember or chassis beam. Be sure not to jack the car up on any other part, as you could put a hole right through the bottom of the car. I have seen Porsches in the past where jacks have punctured the floorboards. A handy reference is Wayne’s article on jacking up your BMW.

Now jack up the front wheels of the car as well. We will want to get the car as level as possible in order to drain all the old fluid out of the differential.

Now crawl under the car and look at the differential. On the very rear of the differential towards the bottom, you will see two 17mm internal Allen head plugs (NOTE: the size can vary with the year and model of your car). These are the drain and filler plugs for the oil. Put a suitable drain tray under the plugs and first open the top plug to relieve any possible vacuum inside the diff and help the oil drain out. Now loosen the lower plug and thread it out by hand. Keep in mind that the old oil will start to flow out as soon as you remove the plug, so make sure the drain pan is directly below. Also, gear oil is some of the worst smelling stuff on earth. If you get any on your clothes, you will never get the smell off again, so be sure to wear your worst work clothes or just work naked! Well, maybe that’s not such a good idea.

Anyway, let the old fluid drain out of the car completely just watch it, it will go from a full stream to a small trickle then it will stop flowing. Once it has stopped, thread the drain plug back in and torque it to 41 ft./lbs. Now, get the new fluid and using a siphon, pump the new fluid into the filer hole at the top. When the fluid begins to flow out of the top hole, it is full. Now re-install the filler plug and torque it to 41 ft./lbs.

Be sure to check your owner’s manual as to what oil to run in the differential. I always use Swepco oil. This stuff is great, it keeps the diff cool, lubricated, and most of all, quiet!

Now lower the car off the jack stands and take your car for a spin to work the new oil into the gears.

Automatic trans. flush on BMW e34

Cost: $15



Automatic transmission without pan, exposing its metal filter

Procedure for changing the fluid and filter on a 4hp22 automatic.


  • 3 qt of ATF fluid.
  • Ramps or stands.
  • Allen wrenches and torx screwdriver.
  • Brake cleaner spray.

1. First raise the car up and place on suitable jackstands or ramps.
2. Place drain pan under and remove metric allen bolt in the center of the pan. Do this with the fluid warm, so it drains more completely. Avoid burning yourself on the fluid.
3. Remove the large nut holding the dipstick tube and move the tube back a 1/2 inch or so.
4. Remove the 6 perimeter bolts and brackets on the pan, making note that some of the brackets are angled for the corners of the pan. Lower the pan.

5. Clean the pan out with brake spray cleaner and clean the two rectangular magnets in the bottom. Replace rubber gasket.
6. Remove the three torx screws that hold the filter in place and change the filter making sure to replace the oring on the top of the filter.
7. Re-install the pan and the filler tube and fill the transmission with fluid.
8. It takes approximately 3 quarts on a filter change. Dexron ii or Mercon.
9. In the future I would change the transmission fluid at every oil change since it only changes 50% of the fluid in it.

Flex Disc & center bearing on BMW e34

Cost: $15

Procedure courtesy of Al Gray, Pictures from Steve Venn
If your driveshaft is staring to make some noises when you take off or at low speed, it is time to get a close look at it. Sometimes changing the flex disc and/or the center bearing will do the trick. Sometimes you will have to change the whole driveshaft and bite the bullet.


My weekend project was the replacement of the flex disc and the center bearing support on the driveshaft of my 1992 525i. I want to personally thank Winfred Dixon for his excellent comments, advice and support for this project.
My car was making the usual progressively worse noises associated with driveshaft related problems. I just didn't know how bad the flex disk was until I looked at my new part and compared it to what was left; basically just the bolts in the steel sleeves surrounded by the remnants of the rubber and strings of thin cord that was imbedded in the rubber. I am amazed the car even moved!

Before attempting this project I purchased a 3 1/2 ton floor jack and 4 substantial jack stands. The Bentley manual mentions at 1/2 page intervals that the car should be on jack stands at the jacking points before getting under the car.
The reason I wanted to attempt this job was primarily to save several hundred dollars but also to prove to myself that I could do it. BMWs are made well but they can also be a tough to work on.

The BMW stealer wanted $110 for the flex disk and $88 for the center support bearing. I paid $39.95 and $32.00 respectively for the parts from BMA. I also needed to order 6 new self-locking nuts for the driveshaft and 6 self-locking nuts for the flex disk; I ordered them from the stealer for a cost of $8.00. The floor jack I picked up for $60.00 and the jack stands cost me $62.00. I also picked up a 19mm combination box wrench and a 1/2 inch drive 19mm socket for a total of $14.00. Lastly, I purchased a 1/2 drive 1 1/4 extended socket for
$7.00. My total costs including the tools I purchased was $222.95


1. The first thing was to raise the car up with the floor jack. I positioned it under the rear differential and raised it up approximately 20 inches. The jack stands were then carefully positioned at the jacking points on the body just in front of the rear wheels. For the front of the car I positioned the floor jack on the cross member just behind the oil pan making sure I did not touch the oil pan and raised the car approx. 20 inches and then positioned the jack stands under the jacking points on the car just behind the front wheels.
2. The next thing to do was to lower the exhaust as much as possible. The Bentley manual says to remove the exhaust, however, that is a lot of work and not necessary. Before lowering the exhaust I positioned the floor jack under and just touching the rear muffler. Working from the rear muffler there are two muffler clamps that require a 13mm socket. Moving forward and just before the center resonator on the exhaust there were two more muffler brackets requiring a 13mm socket for removal. Finally, there is a bracket at the front secured to the rear of the transmission that required a 13mm socket to loosen the two bolts. Once everything was loose, I slowly lowered the exhaust with the floor jack as much as possible but still supporting it.
2. Next was the removal of the heat shield. There were approximately 6 bolts that required either a 13mm socket or 13mm combination box wrench. Once the bolts are out you need to finagle the heat shield out and put it on the floor
and out of the way.
3. The next item was the removal of the bolts from the flex disk. Keeping the car in park (I have an automatic trans)I found that BMW really puts these bolts in tight. I couldn't even budge them with my breaker bar. Using my 19mm wrench on the nut and 19mm socket on the bolt, I finally broke the nut loose by sliding and 18 inch piece of pipe over my wrench for some leverage. To access each bolt I had to turn the driveshaft by hand after taking the car out of park and repositioning my wrench.
4. The next job was to remove the nuts from the rear of the driveshaft. Before you remove the driveshaft paint on marks where it pulls apart for proper alignment when being reinstalled. They required a 13mm wrench and the length of pipe to break them loose.
5. The center support bearing was next. It was held in place by two bolts that require a 13mm socket.
6. Once the driveshaft was loose, I lowered the exhaust a little more and worked the driveshaft out and onto the floor.

7. Although my center bearing was not damaged, at the suggestion of Winfred Dixon I replaced it anyway, just in case. The center bearing is pressed on between the front and rear drive shaft. In order to access the center bearing, the front and rear drive shaft have to be taken apart. There is a 19mm bolt that holds them together. Before taking the driveshaft apart I pained marks on the front and rear driveshafts near the center bearing for proper alignment later. I had to put the rear of the driveshaft in my bench vise to work on this. The bolt holding the two together is really in there! Using my 19mm box wrench with the 18 inch pipe slid over the wrench for leverage, I finally broke it loose. The bolt was a tough out requiring small turns and effort to the last thread. I needed to take a few turns and tap the rear of the driveshaft to loosen it from the front spline until it finally came off the spline. The center bearing is pressed on over the spline. I used a hammer and an old dull chisel to carefully loosen the center bearing and then slide it off.
8. Replacement of the center bearing was easy; you just have to make sure that it is positioned correctly. I used my 1/2 drive 1 1/4 inch extended socket to firmly tap the center bearing into place.
9. The driveshaft was now ready to be bolted together. I put a little CRC on the inside threads of the spline to make putting the bolt in a little easier. Positioning the front and rear driveshafts according to the painted marks, I bolted them together in the same fashion as I took the bolt out. Be sure that the bolt is tight.
10. Now the driveshaft was ready to be installed. I bolted the rear of the driveshaft up first using the new 13mm self-locking nuts. You can access 3 of the bolts at a time. I had to position a screwdriver through the area where the front and rear shafts meet to keep the drive shaft from turning while I was tightening the bolts. Also, I found it easier to mount the center bearing only putting the bolts in finger tight during the process.
11. Next was to intstall the flex disk. In order to do this I had to unbolt the center support bearing so that I could slide the front of the driveshaft into the center bearing and onto the transmission spline. Its important to note that there is a certain way that the flex disk is installed. There are 3 flanges on the front drive shaft that will positioned at the rear of the flex disk and 3 flanges that are on the transmission spline that will be positioned at the front of the flex disk. The flex disk has arrows imbedded in the rubber that point to either the front transmission spline or the rear drive shaft spline. Those arrows need to aligned correctly. Once done, intstall the bolts and nuts and tighten appropriately with 19mm wrench and socket wrench.
Note from Rich W.
One comment - on the page that describes the replacement of the flex disk and center support bearing, the work description skips over the need to avoid torquing the bolt on the "soft" side of the buigo. As you know, putting serious torque to the end of the bolt on the disk side rather than doing your wrenching on the flange side places a serious strain on the cord in the guibo, leading to premature failure. Not good!! This should be included I think.
Finally reinstall heat shield, exhaust brackets and lower car.

NOTES from Peter H.
I used my Bentley manual and your website for reference. Both are great resources. This is the first time that I have ever encountered any discrepecies in either the book or your website. I had the driveshaft off and was looking for the collar to loosen to separate the two halves of the driveshaft at the spline and there was none! I looked at it, consulted both pages in the book and the website because I figured that I must be missing it, but it wasn't there. So off to the dealer with driveshaft in hand. I got there and talked to the sevice manager and he said sometimes you have to replace the driveshaft!! They took it, said it would be about 1.5 hours labor after they looked at it and said they could call when it was done. They called later in hte afternoon and said it was done with a bill of 148.35 for labor and shop charges. I also had them press off and install the new centerbearing while they had it since I could not separate the shaft myself. In all I spent about $220 for everything and it works great. I just wanted to tell you so that the website could let everone know that if they take this on, while a fairly staight foward operation, they might have a little problem with the driveshaft. Thanks for all the great information. I hope I could be of some help to other people that love their cars!!
Thank you,
1993 e34/m50

Clutch hydraulic on BMW e34

Cost: $50


The Bmw E34 clutch is hydraulically piloted by a master and a slave cylinder. No adjustment is needed or possible. The hydraulic clutch uses brake fluid. There's no such thing as "clutch fluid" - you'll get laughed at if you go into an auto parts shop asking for it.
A leak can often be seen at the reservoir/clutch master cylinder, at the other end of the clutch hydraulic line, at the clutch slave cylinder, or inside the car behind the clutch pedal.

Failure syndromes:
• Clutch pedal all the way to the floor, impossible to change gears.
• Clutch reservoir is consistently low you probably have a leak.

Warnings: Take care not to spill brake fluid on yourself or the car's paint - it's highly corrosive. Wash your hands and wipe any spills with a rag.

Master cylinder
  • 10mm flare nut brake wrench (like a closed end wrench with an opening).
  • WD 40.
  • Brake fluid and syringe.

1. Remove the brake fluid inside the brake reservoir, using a clean syringe.
2. Inside the car, remove the plastic cover above the pedals.
3. The master cylinder is above the clutch pedal. To remove the fluid out of the master cylinder, you can disconnect the hose of the slave cylinder and press the clutch pedal.
4. Loosen all the bolts holding the master cylinder then remove the eccentric bolt connecting the cylinder to the pedal, remove the remaining bolts.
5. Disconnect the hose coming into the middle of the cylinder. The tricky part is to remove the lower bolt, holding the metal clutch line: you HAVE to use a special brake wrench (flare nut wrench) and WD40. This nut is hard to loosen and I found it not accessible from the engine compartment, I pulled a little bit on the cylinder from the inside (in an uncomfortable position) and used the wrench to loosen the nut.
6. Install the new cylinder and adjust the eccentric nut for clutch pedal height.
7. Fill up the brake reservoir with new brake fluid and bleed the clutch.

Slave cylinder
  • 10mm flare nut brake wrench (like a closed end wrench with an opening).
  • WD 40 and 13mm socket and ratchet + 13mm closed end wrench.
  • Brake fluid, syringe and pan.
  • Ramps or stands.

1. Place the car on ramps or stands. Remove the brake fluid inside the brake reservoir, using a clean syringe.
2. Under the car, loosen the clutch line nut (if you can), then remove the 2x 13mm bolts holding the cylinder to the transmission. For the top one, I used a ratchet with a 13mm socket a U-joint and an extention.
3. Place a pan under the transmission to catch the brake fluid then detach the metal line from the cylinder.
4. Replace the cylinder with the new one, lightly grease the plastic tip of the pushrod with molybdenum grease and put everything back in place.
Never ever push the clutch pedal with the slave cylinder removed! (I did it once...)
5. Bleed the clutch. (good luck if you don't have a pressure bleeder)
Bleeding procedure
Bleeding is easier if you have a brake pressure bleeder, but it is feasible without fancy tools.
Bleeding the clutch is done at the slave cylinder's end. The procedure isn't the same as bleeding brakes. Do as if you were bleeding brakes than you will feel that the pedal doesn't come back. If this happens, bring the clutch pedal up, unbolt the slave cylinder and let the cylinder rod extend itself. Then put it back in place. This will force the brake fluid inside the cylinder.

Differential swap on BMW e34

Cost: $500

Procedure and photos courtesy of Jeff Bosonetto

The original '95 BMW 540i6 came with a 2.93 open rear end. Many owners wanted a little more zip around the urban streets without giving up too much top end (& gas mileage on the highway). Many owners recommended swapping out the 2.93 for a 3.15.
The 530i diff will not work on the 540i. The input shaft itself is different in diameter & splines and there isn't an input flange available to interface the 530 diff with the 540 driveshaft (different bolt pattern etc). The 530 diff is interchangeable with the 535/525 models of Bmw E34 cars however. For the 540, look for an M5 or 750 diff.
The 3.15 limited slip can be found in the 88 750iL. There is a big question as to whether the LSD rear end would play well with the ASC+T system. Most owners agreed that under normal (non racing) conditions that the two systems would work together. They also agreed that if racing or doing the sometimes needed high speed power slide turn, turn the ASC+T off.

If you would like to know what kind of diff is installed in your car, refer to the data tag located on the rear driver's side of the diff. "S3.15" means a LSD 3.15 diff while a "2.93" means an open end 2.93 diff.

Click on the picture for larger version.

click for larger picture
The diff swap is strait forward except for the diff front shaft flange. This is the part of the diff that bolts to the drive shaft. If the 3.15 diff came from a 750iL then the front flange must be changed. The most important part of the flange swap is resetting the preload (torque of the nut that holds the flange to the diff). Almost all owners recommend having the dealer or a mechanic with the right tools set the preload. If it is not set correctly, the diff will fail in about a year. In the figure the 540i flange is on the left while the 750iL flange is on the right.
Removal Procedure
Since the rear diff weighs about 95 lbs, the first step was to come up with a way to swap out the diff if a second person wasn't available. The design of what became known as the "Differential Extraction and Insertion Device," or "Diff Lift" for short, can be seen in figure 3. The outline of the diff was traced on to one piece of ½" plywood. The plywood piece were screwed to two ½" pieces of particle board and notches were cut into the sides of the plywood to secure the bungee cords. The bungee cords work well in this application since some tweaking while extracting and inserting the diff is required. Secure the Diff Lift to the cup of a floor jack with 8 tie wraps. The floor jack is then used to lift and lower the diff, see picture.

Start by removing the 6 drive shaft nuts. Since a socket wrench will not fit into the area needed, use a 16mm open end wrench or open end socket attachment. Since these are lock nuts they must be replaced with new ones (the dealer or any part store has them). Put the car in gear to lock the drive shaft in place while loosening the bolts. Take the car out of gear to rotate the drive shaft to the next nut. Note that the drive shaft bolts cannot be removed. The Bentley book recommends hanging the drive shaft from the car body using wire. On the 95 540i6, the exhaust system runs right under drive shaft and offers adequate support.

Using an 8mm allen wrench (preferably an allen socket attached to a pneumatic socket wrench), unbolt the half shafts (6 bolts each), see figure 7 . Use the parking brake to hold the shafts in place while loosening the bolts. It is recommended that both sides be done at the same time to reduce the amount times needed to operate the parking brake. More than likely these are the locking style nuts and must be replaced. Support the half shafts with wire or allow them to lie across the suspension.
Disconnect the speedometer wire (located on the rear of the diff, passenger's side). Position the Diff Lift under the diff, barely touching the diff (you want to support the diff while unbolting it but you don't want to bind the bolts).
Secure the bungee cords around the diff. Unbolt the single front mounting bolt (located on the passenger's side of the drive shaft) using a 19mm socket, open end wrench, or open end socket attachment, see picture. Before you unbolt the two rear mounting bolts make sure the diff lift with bungee cords is in place or an extra set of hands are in place. Also note that the rear of the diff must come DOWN first to clear the mounting bracket and then slide back to allow the input flange to slide off of the drive shaft bolts.
The drive shaft flange will articulate to compensate for the angle in which the diff comes out. Next, unbolt the two rear mounting bolts using a 19mm socket. Remove the diff.
Next, if the front input flange from the 3.15 must be swapped out, use a marker and index the bolt position with the nut. This is a good reference when you put the correct flange on and set the preload. The marks should line up pretty close if not right on.
The book recommends replacing the rear end fluid after the diff is reinstalled. This is not exactly the easiest way to do it. Several mechanics recommended changing the oil before reinstalling the diff by leveling the diff on the ground with shims and then adding the oil. Don't forget many rear end oils require an anti-rattle additive. The 88 750iL 3.15 LSD requires 2 qts of hypoid SAE 90/GL-5 LSD rear gear oil. The drive shaft and diff flanges are packed with grease. Repack the diff flange with grease.
Installation Procedure

Please note that the tightening torques recommended below come from the Bentley Book. When the diff is reinstalled be sure to line up the diff front flange holes with the drive shaft bolts. Insert the front of the diff first and make sure all of the drive shaft bolts go through a hole in the diff flange. Next, rotate the rear of the diff up and into position. This requires some careful tweaking. See figure 10. Insert the rear mounting bolts and the front mounting bolt. The recommended torque for the rear bolts is 77nm/57 ft.lbs. The recommended torque for the front bolt is 123nm/91ft.lbs. Note that a standard torque wrench will not fit into area needed to tighten the front mounting bolt. A recommend procedure for torqueing down the front bolt is to use a open end socket attachment on your torque wrench. This will increase the wrench approximately 1 inch. Reduce the required by approximately 1-2 ft.lbs. to compensate for this. See picture.

Next, install the drive shaft lock nuts. The recommended torque is 64-70nm/47-52 ft.lbs. (see the Bentley book). Once again a standard torque wrench will not fit into area to tighten these nuts. Use the procedure recommended for the front mounting bolt to tighten the nuts. Use a cross tightening pattern (like what is used for wheel lug nuts). Once again, put the car in gear to lock the drive shaft in place while tightening the bolts. Take the car out of gear to rotate the drive shaft to the next nut. Mark the nuts with a marker as a reminder as to which nuts have been tightened. Reconnect the speedometer plug. Reinstall the half shaft bolts using 83nm/61 ft.lbs. Use the cross tightening pattern. Once again, use the parking brake to hold the shafts in place while torquing down the bolts. It is recommended that both sides be done at the same time to reduce the amount times needed to operate the parking brake.

Recheck everything, lower the car and enjoy.

Output seal replacemt on BMW e34

On the Bmw E4 after a lot of miles, seals tends to wear and leaks appear.

Failure syndromes:
• Drops of fluid on your garage floor.
• Oil around the drive shaft.

If you still have a leak after changing the seal, you have to change the output flange.

  • 13mm socket
  • 30mm deep thin wall socket
  • New self locking nuts for output flange/flex and final drive flange
  • Output shaft seal
  • Penetrating oil
  • Thread sealer

1. Remove exhaust system: remove the entire exhaust system as a unit. There is no need to take it apart in sections. First, remove nuts that hold the exhaust pipes to the manifold (it may be a good idea to spray with a penetrating oil a few minutes before you start.) Place a floor jack under the catalytic converter for support. Remove mounting nut a third the way down the exhaust assembly. Remove the two rubber hangers from the center support near the catalytic converter (may need to loosen the brackets on the underside of the car via a nut.) Consider replacing these rubber hangers during re-assembly. Remove rear hangers near the rear left fender (one on either side of the muffler). Slide assembly toward rear of car and have a helper guide the front of the exhaust system to the ground.
2. Remove heatshield by removing bolts that hold it onto the underside of the car.
3. Remove driveshaft: remove lock nuts from flex-disc as well as bolts. Remove locking nuts from final drive flange. Remove center bearing support. Move center bearing support to one side so that front of driveshaft comes off of output flange centering pilot. Remove driveshaft. Consider replacing u-joints and/or center bearing at this time.
4. Remove old seal: remove output flange by loosening large nut (30mm) with a deep, thin-wall socket. One might make on of these by grinding down the sides of a regular deep socket. Using a gear puller, remove the flange from the shaft. Remove seal by prying it out with a screwdriver.
5. Install new seal: lube outer side of seal with automatic transmission fluid. Use a large socket or short piece of PVC pipe with end cap attached to drive the seal into the end of the transmission. Be careful to put equal pressure on all sides of the seal so that it does not go in crooked. If the seal goes in wrong, get another one, don't try to reuse it if it appears damaged in any way. Coat splines of flange and threads of output shaft with thread sealer and reinstall flange. Install nut and tighten to specified torque.
6. Install driveshaft using new lock nuts (in reverse order) and tighten all to specified torque.
7. Install heatshield.
8. Install exhaust system in reverse order taking care to tighten nuts sufficiently to prevent any leaks from manifold.

Leather treatment on BMW e34

After 5-10 years, the seats of your Bmw E34, E32 will probably look like mine, with small cracks and discoloration. It is time to renew this leather.
I bought my products from Leatherique.

  • Leatherique products
  • 300 and 500 grits sand paper
  • Terry Towel or soft cloth
1. This is my seat before applying the leatherique products. You can see the difference of colors and little cracks.
2. Vacuum the surface of the seats well or use a soft brush to remove large particles of dirt, paying particular attention to seams, folds, and cracks.
2. Apply the Rejuvenator product on all seats with your bare hands, massaging the leather.
3. You have to let the car sit in a warm spot (sun will be perfect)to have a greenhouse effect, for a day. In cooler weather, or for long-term storage in a garage, cover the seats with plastic wrap, and "warm" with a hair dryer.

4. The seats absorbed the product and the leather is softer. What you see is simply the dirt, grime, air pollution, perspiration, salts and other toxins that have floated out of the leather to the surface.

If you don't dye the leather, Apply Prestine Clean by hand or with a soft Terry Cloth towel and massage out the dirt.

5. Using 300 grit, lightly wet sand the leather to smooth out any cracks and hangnails in the surface, and to remove the surface of the old dye and as much of the old dye that is loose and worn from age. Do not attempt to cover over damaged dye.
6. Apply another coat of Rejuvenator as the seats will absorb it right away.

7. Apply the Prepping Agent liberally with a terry towel or shop rag, and clean to remove any remaining dirt, ensure the top layer of old dye is broken down. Resand with wet 320 if needed . If you are filling cracks with crack filler, this is the time to do that step. Apply crack filler only into cracks only. Allow to dry 20 minutes and refill as necessary. Resand with 500 for a smooth, flawless finish if needed. Let it sit overnight or about 6 hours to allow prepping agent and crack filler to dry.

8. Brush (top quality synthetic, acrylic type brushes) or spray on your new dye in a dirt free environment, preferably indoors. Thin dye to prevent heavy buildup of color. Temperature of 20-30C (70-85F), low humidity, no rain.
9. Let it sit for 48 hours then buff it up with a lint free cloth. Use Prestine Clean in the future for maintenance (in a year).

10. The only mistake I have done is that I should have cut the die with water, it was too thick so you can see the brush pattern. I sanded the seats with 500 grits sand paper until the seats are smooth to the touch... hummmm, I love that.