I don't want to resurrect a dead thread, but I need a little help and hopefully this will get a little visibility.

Motul MotylGear 75W90 meets GL-5/GL-4. Is this safe to use in our manual transmissions? I'm asking because a vendor here sells it specifically for the R56S. I bought 2 liters of it and replaced my gear oil last October. Now my transmission pops out of 6th gear when it is under load. Didn't have a problem before, and didn't notice it until recently because I didn't do much highway driving. It is pretty random, sometimes it holds, sometimes it doesn't and it happens way more often in sport mode. Made 6th totally worthless last weekend at Road Atlanta. The car is a 2013 R56S.

I'm necessarily blaming the fluid, but I would like to know if I screwed myself on this one.

So I'm thinking that if the transmission is bad this would be a good opportunity to add an LSD, since the transmission will be out anyway. According to RealOEM R55-R61 share a transmission. JCW, S and Justa models all get the same one, right? Theoretically, I could get a used low mileage Justa transmission and it should work, right? This car is leaving the daily driver world and transitioning to a track toy for time trial and time attack.

PROBLEM SORTA SOLVED.

​​​​​​I replaced the gear shift with a CAE ultra shifter. The stock shifter housing is mounted to chassis with rubber bushings. The rubber bushings allowed the shifter to move under load and pop out of gear. The solid mount of the CAE prevents the shifter housing from moving and the transmission now stays in gear.

PROBLEM SOLVED (AGAIN).

About six months after I thought I fixed it, this issue started up again. As it turns out my upper engine mount was the problem. I had planned on replacing the upper engine mount and transmission mount with new ones last year but had kind of put it to the back burner. The new mounts have been sitting on my workbench staring at me since then. About a week ago I was feeling antsy and ordered some liquid polyurethane. The plan was to fill the new mounts with poly and install them, but I decided to go with 3M Window Weld instead. I figured if I like the Window Weld, I would poly fill the old mounts. Needless to say in the course of installing the new mounts I discovered that the engine mount was super floppy. The transmission mount was in much better shape, but still on the soft side. The new Window Weld filled mounts have solved the problem. We'll see how they hold up. I still plan on poly filling the old mounts, but I may just order new mounts for that (again).

 

For those interested, I switched to Redline MTL. No change, still intermittent 6th gear issue. I'm going to check the shift linkage and then probably accept that I need a new transmission. I will most likely grab a used low mileage tranny on the Bay of E, toss a Wavetrac LSD in it and go from there. I guess I'll be crossing "dropped a subframe and replaced a transmission" off my bucket list. Might as well upgrade the clutch and put in a lightweight flywheel while I'm at it.

 

 

I changed the transmission oil this summer after getting the car back from an accident. I used 75-90 synthetic Lucas. I have been driving it for about 1500 miles since and now it suddenly is popping out of sixth under load. I have ordered but not yet swapped the fluid for some 75-80 Redline but I am guessing that from your experience, the fluid change will not help and I am destined for a trans swap.
Is there a follow up to how your R56S turned out? I am dealing with a 2009 MCS that has been a real sweet car (118,000 miles) and I'll put the transmission in it if I have to. A winter project once I get some other things in life under control.

 

What is the status of your 2013 r56s? I have a 2009 MCS that I changed the trans fluid in, using Lucus 75-90 synthetic. After 1500-2000 miles, it is now jumping out of sixth gear under load. My experience would tell me I need to work on the transmission or replace it. I am going to try changing to 75-80 redline fluid first but I am not optimistic. Your post said you tried that and it did not have good results and you were going to change transmission. Is that the end of story?

 

ESC tuning? Could the "wrong" (Lucas Synthetic 75-90) transmission fluid cause sixth gear to start jumping out of gear? I am still researching and looking for some experience online that points me to any alternative to pulling the transmission.

 

Sorry for the late reply. Unfortunately, there has been no change to my issue. I replaced the Motul fluid with Redline 75-80.

When I'm back in town I plan on inspecting the motor and transmission mounting points and possibly removing the BSH solid mount and going back to stock to see it that is the issue.

 

I also modified the rear engine mount and could remove it. the fact that the transmission is jumping out of 6th would indicate damage is already done. Comparing the shifting from my 2011 Justa shows that the MCS feels like it isn't quite engaging. I have more investigation to do but will keep you up to date. I probably will have a winter transmission change.

 

I'm with you on that. Time to change the transmission, I think anything else is just me lying to myself lol

 

Generally I never recommend replacing the transmission lubricant with an oil containing friction modifiers. Unless your running a clutch style LSD and the noise is driving you nuts. Our syncros besides matching speed also help hold the gear once engaged. Removing the built up smutz on them while simultaneously making them more slippery can cause a problem.

Something else you can try is mixing 1 qt of 75W-90 with 1 qt of 75W-140. Examples would be SGO 75W-90 plus their 140 (what I run) or
Motul Gear 300 plus Motul Gear Competition. Just my two cents.

 

I have purchased a LSD 6 speed and hope to have a succesful winter project. Waiting for it to get here but everything should work out. I have to work through some family issues, selling the childhood farm, and then time to get busy wrenching.

 

Problem solved. I replaced the gear shift with a CAE ultra shifter. The stock shifter housing is mounted to chassis with rubber bushings. The rubber bushings allowed the the shifter to move under load and pop out of gear. The solid mount of the CAE prevents the shifter housing from moving and the transmission now stays in gear.

 

Sweet bit of kit When I replaced my shifter with the Cravenspeed short shifter I also used their box which sits lower and comes with billet aluminum bushings to replace the soggy rubber ones. Tightened up everything nicely but nowhere near as nice as the CAE.

 

I was shocked at how floppy the rubber mounted box was. All of the sudden it all made sense lol

 

PROBLEM SOLVED (AGAIN).

About six months after I thought I fixed it, this issue started up again. As it turns out my upper engine mount was the problem. I had planned on replacing the upper engine mount and transmission mount with new ones last year but had kind of put it to the back burner. The new mounts have been sitting on my workbench staring at me since then. About a week ago I was feeling antsy and ordered some liquid polyurethane. The plan was to fill the new mounts with poly and install them, but I decided to go with 3M Window Weld instead. I figured if I like the Window Weld, I would poly fill the old mounts. Needless to say in the course of installing the new mounts I discovered that the engine mount was super floppy. The transmission mount was in much better shape, but still on the soft side. The new Window Weld filled mounts have solved the problem. We'll see how they hold up. I still plan on poly filling the old mounts, but I may just order new mounts for that (again).