T-10 4 speed

[Don C.]

I have been working on my frame off restore 1960 corvette
for almost a year. This weekend I drove the car for the first time. One thing I picked up on was how much winding noise the T-10 4speed would make in 1st 2nd & 3rd. (4th gear although was quite in compersation.) Is this comon for this transmission ? I'm running 90lb gear oil in transmission and have been told to add STP?

[Edward J.]

Re: T-10 4 speed

Don, generally the T10 trans will have alittle gear noise as most do. Was the transmisson, rebuilt? from what your saying it sounds like the small needle brgs. where the input and output shaft meet.

[Don C.]

Re: T-10 4 speed

I'm in Alpine, CA. The transmission was purchased from an NCRS member from San Francisco. He was very helpful in answering my questions and gave me receipts from the rebuild. I feel comfortable that the transmission was rebuilt but not 100% sure.

[William C.]

Re: T-10 4 speed

I'm with Ed, sounds like countergear bearings. How significant was the rebuild?

[B C.]

Re: T-10 4 speed

Sounds serious Don...I have to agree, probably countergear
bearings - something may have slipped on assembly.

I recently rebuilt my T10 in a 61 Impala and it is very quiet
except for the slight trans noise in neutral, there is nothing
while in gear and moving.

Only put STP in a manual trans if you don't want to shift when
it is cold.........I learned this from experience many years ago.

If the trans has good parts and put together with a high perf
gear oil, it should not be noisy.

BJ

[Richard G.]

Re: T-10 4 speed

The reason forth gear is quieter than the rest is the power flow is straight through the transmission. Meaning no power is transferred through the counter shaft. When power is transferring through the counter gear you are getting the noise. Remember the counter gear is always rotating but not always transferring power. I suspect the transmission is quiet in neutral, with the clutch out, also.

I have never observed the needle bearing going out on one of these four speeds. The have a large surface area and it the transmission has lube they are rarely an issue. A missing or incorrectly sized pilot bearing will defiantly cause the symptoms you have. What is the history on this bearing (bushing on early Corvette's) I wish I could hear the transmission noise as a bearing defect has a special sound of it's own and is somewhat different than gear noise. Does the noise pitch change with the speed of the Corvette or the RPM of the motor? Sometimes the builder is lazy and fails to change out the center bearing as it requires the main shaft to be completely torn down.
I would bring it to a transmission shop and have them drive it before tearing it down so they can listen to the sound and symptoms that we can't. Also drain the oil if it has a drain plug and check the condition. If not pull the driveline and check the condition of the oil that way. If it has issues it may show up on the oil. Infant mortality can be an issue on any rebuild.
Best of luck
Rick