Captain_Kaboom

Hey guys- they've got my '77 up on the rack for an alignment jobbie. The guy working on it noticed there was some play on either side of the differential when the weight of the car was off it. Is this normal or something that I have to be worried about?

Thanks!

Van Steel

You should check your side yokes. Since it's a posi car the yokes rub against the center pin and they wear down causing play.

Captain_Kaboom

Thanks! Anyone have any pics or how I can tell what condition my yokes are in? (or even what to look for. Please, no egg jokes) If they are worn down, what are ramifications? Do I really need to replace it?

FeedVaal

"High Mileage Club Member @ 138k"

Trust me, they're worn.

Jvette73

My diff lost one of the snap ring retainers from the side yoke. The alignment guy pointed this out to me and would not proceed with the job. I took the car back and fixed the snap ring myself then took it back for alignment. Of coarse I had to pull the diff to replace the .59cent snapring. havnt had a problem with it since. I foung the old snapring in the diff oil in two chewed up pieces. Everything else looked fine so I was lucky it didnt tear anything else up. Ive swapped new gears in since then anyway. If you have to pull the diff for a side yoke problem, nows the time to think about a gear swap. Dont do it twice loke I did. :cheers:

jerryp58

You should search the archives, there are lots of threads on this and some quote the spec.

You can have some play, but I can't remember what the spec is on movement for the differential yokes (but I believe it's small).

Mine were bad, really bad. If you see something that looks like this (notice the freshly scored metal above the U-bolt nut) http://users.erols.com/jerryp58/corv...earproblem.jpg , then your yokes are in really bad shape too.

I'd guess there's about 1/8-1/4" of metal from the end of the yoke to the snap ring. Well, all of that and then some, was gone on one of my yokes. All that metal and the snap ring got chewed up by the gears. Fortunately there was no gear or clutch damage.

Anyway, hopefully, yours won't be quite that bad, but as suggested, after 138k miles, they're probably pretty worn.

Good Luck.

Captain_Kaboom

ummmm (Homer drool) gear swap. That's tempting me to fix. Any problems with letting this go for a bit? I just spent my dough on the alignment and tires. Hehe yeah those old Generals that came on the car when I bought it looked new, very little tread wear, but they were 10 years old and rotten and cracked.

Any idea of costs for replacement side yokes?

jerryp58

If you've lost either or both of the snap rings, you could theoretically pull a yoke all the way out of the differential. But, I think you'd have to get the suspension pretty out of shape to do that.

As you can see in the image I posted above, I was starting to tear up the outer casing.

Other than that, I would think the big worry would be: ruining the gears, ruining the clutch pack, or totally toasting the diff which, I would guess, could cause lots of other problems depending on how tangled up things get (e.g., half shafts stop, drive shaft stops, any one or more of the three break off).

I guess it all depends on how worn things are.

As far as cost. Here's the breakdown for what I had done... http://forums.corvetteforum.com/zerothread?id=503890

Hope this helps.

Captain_Kaboom

Thanks for the posts!

Humm so no bumpy roads, huh?
It doesn't feel like anything is wrong with it while driving- no bumps or thumps- is that typical?

Should I get the differential rebuilt if I replace the yokes? Or can I buy a new one outright with 3.7 gears? Lookin for advice on what to do and where to find the stuff.

Van Steel

They don't make the housings for the rear ends any more. If yours is not torn up inside than it's fine. For the side yoke i believe it a 1/16 or an 1/8 of an inch from the c-clip to the top. One side will always wear more tham the other. 9 times out of 10 if the c-clip wears off the yoke will not just fall out. It mushrooms on the top and you will have to take a heavy hammer and give it a few good wacks. Than it'll pull out. If the yokes are worn badly it be a real good idea to make sure that the gears are not chipped and that your clutch pack is in good condition. A new clutch pack should be put in anyway as a percaution. :thumbs: