Ok, I am changing my 91 Vert from auto to 5speed. I went to the salvage yard and got the 5spd, flywheel, pedal assembly, hyrdaulics & lines and driveshaft from a 91 coupe.

The shifter was tight and felt smooth shifting so I took it all home. I get home and spin the input shaft and go through the gears. 1st 2nd and 3rd are stripped. I take the trans back to get one from a 90 and it will only go into 1st and 2nd. The only other 5spd they had was an 88 and it had broken teeth one one of the gears. It felt rough turning the input shaft so I pulled the tail and found 3 broken teeth.

Are the gears on the NA 5 speeds made from pot metal? I don't even know if I still want one now after seeing 3 out of 3 broken.

Is this common?

 

Did the last one even have fluid in it? How are you doing this test?

 

well nice to see a TR-7 guy. lol

look p te Miata gears in h N/A case it might be a better bet then going to anoth 5spd. im on my 3rd the first one 1st gear exploded and took outpartof second and the 5th/reverse sincro went bad 2nd one 5th/revese sincro went bad and now im on number 3.

 

i think finding 3 fc's in a junkyard is far less common

 

They all had fluid. The test/visual inspection was done on a bench. I put the drive shaft in, spin the input shaft by hand and try all the gears. The first tranny had the 1st-3rd gear totally stipped, ie., spin input shaft and drive shaft does nothing.

 

I'm just gonna switch out all the drivetrain with T2 stuff.

I have got the Trans, driveshaft, diff and axles from an 87 T2. I just need to find an S5 turbo flywheel.

 

Hey Slider, What year TR7 do you have? sig says 70 but Sep. 74 was first production. Is it a hard top or a drop top?

 

its a hard top i knew one of te ws newer couldn' emember which onez(i haved a 1970 porsche and a 74 TR-7 obviously

 

yes, the NA rx7 trannies are weak, and disposable at this point in time.

For that matter even the aisin rx8 6sp trans is not all that strong, and barely holds up to the ground thumping torque that the stock renesis puts out in stock form. And if you drive one more aggressively than "normal" you are bound to destroy synchros and eventually gears.

The last time I had an NA trans in one of my cars, I lost every gear but 4th and had to drive home from atlanta in 4th after making a standing start with a 6 puck clutch in 4th.

 

lol, I bet that thing shuddered like crazy trying to get it moving.

 

I just held it wide damn open and slipped the pedal as slow as I could, I had to repeat the procedure 3 or 4 times to get up to 30mph so I could engage it fully and at that point I was fine as boost built and the car pulled okay. Of course I gave a rat's *** about the flywheel and clutch at that point, since I knew I was going to a turbo drivetrain as soon as I got home (I had one on hand).