Anyone have slight leaking from rear tranny seal after switc

[Rich in Tupelo]

I got the GL5 75w90 out of my tranny this past weekend. I noticed a little MTL on the garage floor (was not their until after I parked the car today. I check each night) tonight. Double checked to make sure it was not from drains.

Rich

[Threeshifter]

I put redline MTL in on Monday and I have noticed a leak. It does not leak when the car has been sitting but after a drive when the car is warm. I plan on getting under there tomorrow to examine. I did some other things though, including having a great deal of difficulty with replacing the shifter shaft seal.

I also replaced the diff output seals and fluid with redline gear lube. I have not noticed any leakage there.

I have noticed a sound difference. I am not sure if it is the transmission or my perception.

[5er Quest]

I've probably read about a billion posts wondering if changing to Redline (or synthetic oil if that's the thread subject) causes leaks. The answer is an uneviquivical "NO". What it might be doing for you is exposing a failing seal. You didn't say if you put Redline in or the same as what came out.

Regarding Threeshifter's noise, most likely NOT your imagination. Changing to Redline does put a little tranny music in the cabin for you. I guess it's better than sluggish shifting in cold weather, tho.

HTH

Tom

[Threeshifter]

Assuming the redline MTL is exposing a failing rear main seal I am guessing that the front main is probably in similar condition. Concern is that the front main might be leaking a little in the clutch. I am not excited about failing the clutch with an oil leak nor am I excited about removing the transmission to replace the front main seal at this time.

If I remove the redline MTL and replace with another GL-5 lube can I reduce/eliminate this leakage and buy some time on the seals? It was not leaking before the redline MTL. Any recommendation for a less-leaky GL-5 lube ( I do not know what was in there)?

[Rich in Tupelo]

Seals on mine are not that old. I did do the shift shaft seal and wonder if it might be coming out their a little during driving but fine when parked? I will keep an eye on the level and amount leaking (quarter sized for now) and go from their over the weekend.

Rich

[Guest]

Rich,

When you replaced the seal did you install it in the exact same position as the old seal ??

If you did, that may be a cause for a slight seep. Anytime I install new seals like those used on the transmission, the rear or front crank seals or the camshaft seal, I purposely don't drive them to the same position as the old seal. The reason is to provide a clean unworn surface for the new seal to ride on.

One other question, did you use coat the splines of the output shaft with a light gasket sealer prior to installing reinstaling the yoke ??

If you didn't, the Redline WILL seep past the splines and drip on your floor.

Rich

[Rich in Tupelo]

Rich,
When you replaced the seal did you install it in the exact same position as the old seal ??

If you did, that may be a cause for a slight seep. Anytime I install new seals like those used on the transmission, the rear or front crank seals or the camshaft seal, I purposely don't drive them to the same position as the old seal. The reason is to provide a clean unworn surface for the new seal to ride on.

One other question, did you use coat the splines of the output shaft with a light gasket sealer prior to installing reinstaling the yoke ??

If you didn't, the Redline WILL seep past the splines and drip on your floor.

Rich

Rich,

A friend of mine who has done several of these did the shifter rebuild at the same time I was working on other stuff so we could get it all done in a day so I can't say if he did or did not. Given the height of the splines to the fill plug, is it critical that I pull and seal at this time or will it be a slight leak for now that I will need to check the MTL levels on? Is their any other way to seal it without pulling the shifter shaft seal again? Will ATF leak in it also? The GL5 75w90 with lsd agent did not.

Rich


[Edit by Rich in Savannah on [TIME]1108744696[/TIME]]

[Guest]

Rich,

I wouldn't worry about it if your just leaving a small dribble on the garage floor. My G265 leaked the same way after I did all the seals and I don't recall ever having to add fluid.

If you switch to ATF you'll probably have the same problem, since the stuff is thin and slippery. I've been told that one can run straight weight SAE 30 or 40 motor oil in the Getrag in place of the GL-4 gear lube. This probably wouldn't leak like the MTL or ATF, and would probably shift much easier than the original GL-4 gear lube.

Rich

[Threeshifter]

Any recommendation for a less-leaky GL-5 lube ( I do not know what was in there)?

Oops, I meant to say GL-4 up there.

[kendogg1]

OK, I'm hearing all this talk about this and that about fluids, but, are there any oils to AVOID for my trans? If the Redline MTL may cause leaks, thast fine, but, will it hurt anything else, or is it really a superior oil to most anything else on the market? Is there anything similar?

[Rich in Tupelo]

OK, I'm hearing all this talk about this and that about fluids, but, are there any oils to AVOID for my trans? If the Redline MTL may cause leaks, thast fine, but, will it hurt anything else, or is it really a superior oil to most anything else on the market? Is there anything similar?

Yes, I would suggest avoiding GL5. Some say that the milspec 2105 in this is fine, but the more I have read the more uncomfortable I was using it. I was also concerned that it was 75w90 and BMW suggested an 80 for the car. So, I chose the 70w80 redline MTL. Others have used the syn. 75w90 with no issues. From what I can tell the biggest concern with using the GL5 is the formula used it the normal non-syn types can sometimes eat the brass syncro's in the tranny over time.

Rich

[Rich in Tupelo]

Rich,
I wouldn't worry about it if your just leaving a small dribble on the garage floor. My G265 leaked the same way after I did all the seals and I don't recall ever having to add fluid.

If you switch to ATF you'll probably have the same problem, since the stuff is thin and slippery. I've been told that one can run straight weight SAE 30 or 40 motor oil in the Getrag in place of the GL-4 gear lube. This probably wouldn't leak like the MTL or ATF, and would probably shift much easier than the original GL-4 gear lube.

Rich

Thanks Rich.

[kendogg1]

OK, I'm hearing all this talk about this and that about fluids, but, are there any oils to AVOID for my trans? If the Redline MTL may cause leaks, thast fine, but, will it hurt anything else, or is it really a superior oil to most anything else on the market? Is there anything similar?

Yes, I would suggest avoiding GL5. Some say that the milspec 2105 in this is fine, but the more I have read the more uncomfortable I was using it. I was also concerned that it was 75w90 and BMW suggested an 80 for the car. So, I chose the 70w80 redline MTL. Others have used the syn. 75w90 with no issues. From what I can tell the biggest concern with using the GL5 is the formula used it the normal non-syn types can sometimes eat the brass syncro's in the tranny over time.

Rich

Yes, I would suggest avoiding GL5. Some say that the milspec 2105 in this is fine, but the more I have read the more uncomfortable I was using it. I was also concerned that it was 75w90 and BMW suggested an 80 for the car. So, I chose the 70w80 redline MTL. Others have used the syn. 75w90 with no issues. From what I can tell the biggest concern with using the GL5 is the formula used it the normal non-syn types can sometimes eat the brass syncro's in the tranny over time.

Rich

So, your saying I should make sure I get a 75-80 GL-4? Are all the redline fluids synthetic, or should I consider non-synthetic? I'm going to be changing out the fluid next weekend, so, I've still got a couple days to decide. Also, is bavauto probably one of the best places to get the oil? Thanks.

[Rich in Tupelo]

So, your saying I should make sure I get a 75-80 GL-4? Are all the redline fluids synthetic, or should I consider non-synthetic? I'm going to be changing out the fluid next weekend, so, I've still got a couple days to decide. Also, is bavauto probably one of the best places to get the oil? Thanks.

based on my personal trial and error, I would suggest using Redline MTL. Like Rich Euro M5 mentioned, it may dribble a little but this is ok. Or, use castrol dexron III ATF which has a GL4 rating (Rich also mentioned a couple of other choices but I have not tried those or know anyone who is running the normal weight oil, but it makes sense). As for source, it is widely available. I bought mine from Bimmerworld by the quart. The one think I like about the bavauto and BMP stuff is you can get it by the gallon and get the pump that lets you do it from below (If I had known, I would have gotten the pump). Otherwise, run a tube from the engine bay to the tranny and pour away. Be sure to wipe clean your exhaust of any spills with simple green or like cleaner or you will get a very smokey engine bay (don't ask How I know this one.. blond moment).

Hope that helps.

Rich

[Threeshifter]

For the record I have found the leak source in my situation and it is not the redline MTL being more leaky and getting buy the seals.

I would be interested in how to reduce the singing noise that you get with redline MTL. I think there are some posts out that suggest a mix with some straight 30 or something?

[Threeshifter]

I would be interested in how to reduce the singing noise that you get with redline MTL. I think there are some posts out that suggest a mix with some straight 30 or something?

I posted a new thread on this subject since it is a separate issue:
Singing transmission with Redline MTL