Author Topic: 3 Speed Trans Rebuild  (Read 2695 times)

stovebolt

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3 Speed Trans Rebuild
« on: November 18, 2007, 01:12:05 PM »
I have a question regarding the synchronizers on my 3 speed trans but this question can apply to 4 speeds also. I'm rebuilding my trans using all NOS GM synchronizers, gears and blocking rings, all in perfect condition. The 1st and reverse synchronizer slides very nicely but the 2nd and 3rd less smoothly. The GM shop manual says that the synchronizer assembly (hub and slider) is a matched set and must be kept together. No problem, I haven't mixed them up. My question is, is the circular location of the slider on the hub matched also? If so, then there's probably a mismatch there as I've removed the slider from the hub without marking the relationship. Is it just a question of trying out the slider on each of the 30 different splines on the hub to find the smoothest combination. Or are there other ways to ensure a smooth sliding action. All comments and suggestions are appreciated. Sorry about the long-winded question, but I want to get this right the first time. Thanks for any help provided.

68Zproject

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Re: 3 Speed Trans Rebuild
« Reply #1 on: January 19, 2008, 05:19:35 AM »
Did you get he spring keepers in evenly?
68Z28

stovebolt

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Re: 3 Speed Trans Rebuild
« Reply #2 on: January 22, 2008, 12:28:50 AM »
Yes, the three keys are sitting properly and the two key springs are not hooked into the same key as noted in the shop manual.

68Zproject

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Re: 3 Speed Trans Rebuild
« Reply #3 on: January 23, 2008, 01:19:20 AM »
I'm not a tranny expert, I've taken a few apart and put them together, but that's it.  My tranny was rebuilt and the sliders were very stiff at first and I could hardly move them by hand.  Now I've got about 500 miles on it and it moves a lot easier.
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Jerry@CHP

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Re: 3 Speed Trans Rebuild
« Reply #4 on: February 01, 2008, 10:45:06 PM »
GM blocking rings are not the best way to go.  98% of them do not fit on the cone part of the gear properly.  You should be able to mix and match these parts all the time.  We do a lot of transmissions at CHP and never had issues like this but we use aftermarket parts from a vendor in Detroit.

Jerry