How to check a 5-spped tranny?

SuperCoupe007

Registered User
Hey guys,
I have a 90 SC 5-speed, and I am planning on going hunting at the local junk yards for a 5-speed tranny. Is there any way to inspect a transmission to see if it is in working order?
Thanks.
:)
 
I don't know if shifting through the gears would really tell you much. If you take off the top cover, you can slide the brass blocker rings (synchros) towards the gears and measure the tolerance. I forget what is the correct tolerance for low wear, but if they move a whole lot - maybe even touch the gear, they're worn out and it will not shift into that gear very well, if at all. If the shifter feels sloppy, it will need rebuilt...which is very common in junkyard sc's.
 
Take the top cover off and inspect the blocker rings on each side of each synchronizer assembly. They are the brass gear looking pieces. They should all be fairly snug and not dangly or really loose, the 2 in the middle (2nd & 3rd gear) especially. If they are real loose the fiber lining is worn off and they'll crunch when shifting. They should snug up to the synchronizer but leave a gap when pushed up to the gear. Check the fluid color and clarity, it's red ATF, and inspect all the gears you can see for any damage. The front input shaft can wiggle side to side a little but not front to back. Hope this helps.
 
Thanks for the info Mike....:D

I have a 5 speed trans with a busted bell housing and was wondering how I could tell if the internals were any good....:p
 
Take the top cover off and inspect the blocker rings on each side of each synchronizer assembly. They are the brass gear looking pieces. They should all be fairly snug and not dangly or really loose, the 2 in the middle (2nd & 3rd gear) especially. If they are real loose the fiber lining is worn off and they'll crunch when shifting. They should snug up to the synchronizer but leave a gap when pushed up to the gear. Check the fluid color and clarity, it's red ATF, and inspect all the gears you can see for any damage. The front input shaft can wiggle side to side a little but not front to back. Hope this helps.

That is great information for me to test on the tranny when out in the yard. I haven't had a chance to go out to the yard, but I hope that soon I can go look for a tranny.

I know its a big long shot, but would you by any chance happen to have a video that demonstrates this? :p

Thanks,
:)
 
No sorry, never thought to do a video but I've got a tranny open now I'm disassembling for parts that I could video. If I get a chance later this week I'll see what I can do.
 
I don't know if shifting through the gears would really tell you much. If you take off the top cover, you can slide the brass blocker rings (synchros) towards the gears and measure the tolerance. I forget what is the correct tolerance for low wear, but if they move a whole lot - maybe even touch the gear, they're worn out and it will not shift into that gear very well, if at all. If the shifter feels sloppy, it will need rebuilt...which is very common in junkyard sc's.

From my factory service manual:

"1. Inspect gear teeth on sychronizer ring. If there is evidence of chipping or excessively worn teeth, replace with new parts.

2.Inspect the sychronizer ring for wear. To check wear of the sychronizer ring, fit the sychronizer evenly to the gear cone. Measure the clearance between side faces of sychronizer ring and gear with a feeler gauge. If clearance is less than 0.8mm(0.031 inch), replace sychronizer ring.

Note: First/second, third/fourth and fifth/reverse sychronizer-to-gear clearance specifications are all the same."
 
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