How-To: Overfill the Evo 8/9 MR (6 Speed) Transmission
This is a walk-through on over-filling the transmission on the Evo 8/9. If you are uncomfortable with doing your own work, please consult a professional.
- 10mm allen wrench
- Heavy-duty Jack & stands
- 2.5 quarts of GL4 75w85 (I use Red Line GL4 75w85 – specially made for the Evo 8/9 MR 6 speed)
- Fluid pump
- Oil pan
About 1500 miles on my TRE built 6 speed, so a little more than due for changing the break in fluid. I’ve changed the transmission a few times now, so all the “built” stuff should have settled down.
The Evo 8/9 MR 6 speed is relatively weak, and thus we want to take extra care to make sure the transmission has enough oil in it. The 6 speed is housed in the same size as the 5 speed, which means less fluid capacity, so we want to squeeze in every drop. Adding as much oil as possible also crucially allows for extra heat capacity.
1. Jack up the Driver’s side of the car. Remove the driver’s wheel. If you have the plastic undertray, uninstall it.
2. The fill plug in the upper left corner. It will be blocked by the undertray if you have it on. It takes a 10mm allen head. Always open the fill plug first:
3. The drain plug takes the same 10mm allen head. Place your oil pan under the drain plug and drain the oil.
4. VERY CAREFULLY, lower the car somewhat until the car is even, to allow the car to drain extra. Do so by very slowly loosening the jack until the car is near even, and retightening. If your jack releases very quickly, skip this step. This is just to get all the fluid out of the transmission.
5. Once it is done draining, reinstall the drain plug. The listed torque spec is 25-30lbft.
6. The key to overfilling the transmission is to jack up the driver’s side as much as possible. Always use a stand, and watch to make sure the car won’t tip over. I wound up getting the car higher than what’s pictured below, actually to the max of what my jack would allow.
7. Use a pump to pump fluid (I used a Plews pump) in. Keep the oil pan under this area of the car. Once it starts to dribble out, give it a minute to work its way down. Continue until every pump results in fluid dribbling out. Once you’re at this point, pump as much fluid in, and quickly reinstall the fill plug. The listed torque spec for the fill plug is also 25lbft. This should result in a little over 2.6qts of fluid in the transmission. The listed capacity is 2.3qts, so at a MINIMUM you should be getting that much in.