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Wedge Trans Oil for TR7 5-Speed ?

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MichaelF

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A few weeks ago I changed out transmission oil of unknown vintage on my '81 TR7. It had been shifting fine so it was just a matter of getting all fluids more or less up to date.

I used 75W Redline rather than the generic brand. Now the shifting is decidely "grunchy" until the car is thoroughly warmed up. It's cooler now but not that cold in WA -- well above freezing.

Is this just cool-weather stiffness? Or is it possible the Redline is just too slippery for the synchros to work?

Any advice appreciated.
 
The recommended trans oil is, believe it or not, automatic transmission fluid. Type really doesn't matter (I used Dextron III).
 
And if you must have Redline (which is what I use), they make automatic transmission fluid too...
 
Don't use normal automatic transmission fluid. The generally recommended fluid is GM Syncromesh or equivelent.

BL had its dealers put ATF in some cars in cold climates due to some gear shift problems when the gearbox was cold. Long term though, the film strength of ATF isn't enough to protect the parts in the gearbox.

Gear oil is to thick for the oil pump in the transmission. It is made out of a fibre material and can be damaged if the oil is to thick.

The above is not from my own experience, but what I have learned from other sources that I believe to be true.
 
I rebuilt the 5 speed in my 79 TR7 late last summer, put gear oil in and all was well, till it got cold. below about 40 deg. F, syncros didnt want to work until warmed up, replaced the gear oil with ATF and all was well.
 
I have been using redline 75/80 in my transmission with no problems, I live in Eugene Oregon and spent last winter in OKC and have driven up to NAS Whidbey Island in the winter. But, I am going to try redline DT4 transmission oil. Good for ATF or synchromesh transmissions (VW, BMW etc) when I get back on the road. It is rated 70/80 and meets GL-4.
 
I use the Red Line D4 ATF synthetic made for auto/manual transmissions. Used it for years with no problems.
 
The Red Line synthetic stuff looks good, probably better than the GM Syncromesh, and you don't have to go to GM for it. =)
 
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