Ok, here’s the back story:
Last summer I participated in Dr. Evil’s SoCal Transmission clinic and with his (and other’s) assistance, I rebuilt my tranny. As I disassembled my transmission, I found the source of my whining tranny sound – badly worn R&P gears…

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Dr. Evil told me my transmission would continue to work, but the whining would only get louder.

So a couple of weeks ago, I found a transmission for sale that was represented to be in good shape, but had been stored for the past two years. I inspected it and it turned, so I took it. Once I got it home, I drained and replaced the GL-5 gear oil and spun it with a drill for about 15 minutes. When I drained it a second time the oil came out pretty clear, with a little fuzz on the drain magnet.

During this past weekend, I replaced my transmission with the “new” transmission. So far, so good. No whine, and all the gears seem to shift pretty good. The only things I think I can improve are what I believe are worn brake bands and dog teeth on third and fourth gear.

So finally, here’s the question:
Can I substitute my rebuilt third and fourth gear stacks from my old transmission to the “new” transmission?

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Or should I remove the brake bands and dog teeth from the old gear cassettes and transfer them to the “new” gear cassettes?

My thanks.

Eric Read

as long as you use the matching ring/pinion/case, the gears can be swapped. I used the best gears/synchros from another box and brought them over to a known good ring/pinion/case and it worked fine.

As Roger said. You can simply swap the gears themselves, but you need to keep the R/P/case/int plate together. The only thing I would recommend is to measure the thickness of the old gears and compare to the new ones. Any appreciable difference in thickness can be adjusted for in the gasket. If there is no gasket made to adjust the difference, it is a negligible difference and you can ignore it.

To add: every tranny i've rebuilt (about 15, 5 of which where R&P replacements), i take obsessive/border line retarded notes as well as copy dimensions. I have yet to see different dimensions on the gears themselves (other than the OD's, obviously the ratio) in these 901/911/914 boxes. then again same as the 915 and G50.

personally, if the gears are in good shape, swap them over. but as DrE says, measure... for good measure. if its an issue, then pulling the dog teeth and syncro isn't the end of the world, just tacking on an extra half hour if you have the right tools.

cheers! d

I just changed a 5th gear last night and it was .002" off. Not appreciable, but over several gears this could cause issue.

Realize also that you will be swapping 1st to a no mated 1sd and 2nd to a non mated second unless you swap the shaft and small 1st gear.

ENJOY!

Thanks everybody. I plan to use the "new" case and only swap the 2nd and 3rd gear casettes form the Evil Tranny Clinic transmission (since I know these casettes have good dog teeth and brake bands). This will have to wait until April, so I'll post a thread when I get ready and post some pics of my progress at that time.

My thanks.

Eric Read

Eric, just have THOMAS swap the teeth and bands for ya. It is easy and he has the special tools local.

Your Evilness;

Great idea! I'll check with Thomas when I get back form Vegas in March. My thanks!

Eric