MTM

I tried doing a search on this, but I only came up with results on LSD transmissions. I filled up the transaxle on my S2 with MT90 a while ago, and now the transmission is more noisy than before. Like, after driving fast for a long time, if I let off the gas and coast in gear, it makes a humming sound. If I disengage the clutch, or put it in neutral, the sound goes away completely. It seems to do it mostly if the car is moving fast and the transmission is all warmed up. Is this normal with synthetic gear oil, or should I be worried about it?

MTM

Bump - anyone get a noisy transmission by switching to Redline gear oil?

Paul C 944

I never noticed anything when I put in mt 90. That was 2 yrs ago

scottz

I have an 86 Turbo with LSD. I switched to Mobil 1 75-90 and it make a large difference in the whining from the rear. From an "annoying" at highway speeds to a "barely noticable" at highway speeds. Not sure what was in there before (was synthetic, could have been Redline) as it was put in by the previous owner.

Flight_951

The only time I noticed a noisy transaxle is when there wasn't enough fluid in it. I'm using MT-90 without a problem. It did quiet a noisy LSD too.

Skip

That's not normal to have MORE noise with MT90. This might be a good time to pull the diff cover and have a look - could be warning signs of a ring-n-pinion about to go. At the very least, if you truly notice more noise lately, drain and strain - have a look at what comes out. Otherwise, these trannies are pretty noisy - I don't think I've ever heard a silent one.

Minus000

I noticed no audible sound level change when switching to mt90

Charlie944

I have had MT-90 in for a couple years, and I should really change it due to there is no filtration sytsem, but I have never noticed more noise. I do notice the torque tube bearings making noise but that is common after even 30k miles.
Hope the noise does not ellude to big prob$.
For reference my 84' has 177k on it and is majoritably highway miles.