5sp Trans Chatter

[Jaymanbikes]

I have a 1977 280z with a 5sp with 75k miles. The car sat up for approx 10 years, I purchased it approx 6 months ago and got her up and running.  The clutch was slipping and had what I thought was a slight throw out bearing rattle.  I had a shop replace the clutch, throw bear bearing and I also had them put a new resurfaced stock flywheel. Within  a week or so I have got a rattle that goes away when the clutch is engaged.  I can also hear it as I am in lower gears moving but seems to go away as I get into 3 and 4th.  The Trans shifts very smoothly.  

It was suggested that I replace the Trans Lube to a Redline oil.  I wasn't able to get it locally so I used a Mobile 1 product.  After the change I didn't notice any improvement.

Looking for suggestions as to next logical step.  Would it be worth ordering the Redline oil and giving it a try.   After reading some of the threads my thought it that it is the input/pilot bearing?

I appreaciate any suggestions and or thoughts!

 

 

[siteunseen]

For what it's worth my throw out bearing whines too, most notable at a dead stop without the clutch engaged.  Exedy clutch kit with the bearing pressed on the collar at a machine shop.  I drove the bearing on myself with my '77 and it's a good bit louder than the last one I had the machinist press on for my '72.  I think the bearing itself is noisy and the transmission being so close to me amplifies the sound.  I can't say mine has a "rattle" though.  Maybe check the driveshaft bolts at the differential?

Hopefully you'll find the cause

[Zup]

Not saying it will fix your issue with your tranny---but it damn sure won't hurt!

[gwri8]

What was the Mobile One product you used?  One of the main reasons for Redline MT-90 is the compatibility for the brass synchronizers.

[Jaymanbikes]

Synthetic gear Lube LS 75W-90

 

https://mobiloil.com/en/gear-lubricants/mobil-1-synthetic-gear-lube-ls

 

[Dave WM]

I use the GL-4 stuff (as per the FSM). Perhaps the mobil oil GL-5 is ok with the brass in the trans, but the reason I used the GL-4 rated MT-90 was for the brass.

I would look into this, found it in the mobil-1 oil  info sheet. Could be a problem as I recall reading that sulfur additives where the issue for the brass.

 "sulfur-phosphorous additive system"

From more reading it seems that modern GL-5 oils are prob fine. I suspect this has been hashed out a zillion times. a google search will get you a lot of opinions.

 

I also suspect the oil is not the issue, but always good to make sure you have the correct type and amounts of fluids in the car.

 

 

Edited November 24, 2016 by Dave WM