Need differential help!
Thread Starter
Race Director
Joined: Dec 1999
Posts: 16,945
Likes: 9
Need differential help!
What is the max. allowed sideplay of the yokes for an 80-82 diff and for a pre80 diff?
A buddy of mine has a 78 w/ about 1/10th " sideplay. Seems a little much.
Yokes are fine, C-clips too. C-clip grooves in yokes are fine, planet gears are fine, the pin in the posi case is fine.
What could cause this?
Thanks,
Marck
A buddy of mine has a 78 w/ about 1/10th " sideplay. Seems a little much.
Yokes are fine, C-clips too. C-clip grooves in yokes are fine, planet gears are fine, the pin in the posi case is fine.
What could cause this?
Thanks,
Marck
Tech Contributor
Joined: Aug 1999
Posts: 15,135
Likes: 3,939
From: Connecticut, USA
Re: Need differential help! (Twinnie)
1/10 is .100" which is justunder 1/8" which is too much play. The rule of thumb I used is .080" max but if you have things apart then why not save yourself time and either repair or replace them. Can you still see the chamfer on the end? If not then the case hardness is probably gone. Also I heard here that the original 77-79 yokes were softer then the older ones and quickly were worn down. Did you check the oil for metal?
Gary
Gary
Race Director
Joined: Aug 2000
Posts: 18,477
Likes: 3
From: Quincy IL
Re: Need differential help! (gtr1999)
GM's yoke supplier from 76 to 79 did NOT heat treat the ends of the yokes,so with a little wear they start hitting,beating on each other,mushrooming the ends.
Thread Starter
Race Director
Joined: Dec 1999
Posts: 16,945
Likes: 9
Re: Need differential help! (Gary79)
You guys were right, I just had him recheck and his pass. side yoke is worn really well so that's the problem. I told him to buy new ones from toms
Thanx
Marck
Thanx
Marck
Le Mans Master
Joined: Apr 1999
Posts: 6,134
Likes: 46
From: Raleigh North Carolina
Re: Need differential help! (Twinnie)
Check the pinion shaft while you are in there.... the yokes ride on it and it will wear as well. The yokes don't "touch in the middle", they ride on the pinion shaft. The best I've ever been able to get new yokes & shaft to set up is at .008 to .010.
Adjusting the carrier left/right for pinion/ring gear setup affects the yoke end clearance... when the carrier moves, so does the pinion shaft. There has to be some clearance to allow carrier adjustment without causing yoke bind.
This is why there is no published spec for this... as the carrier is adjusted, the yoke clearance will change. Some guys add metal to the yokes to get near zero endplay, some guys run without the clips .... this is one of those "gray" areas.
[Modified by Tom454, 7:16 AM 2/14/2002]
Adjusting the carrier left/right for pinion/ring gear setup affects the yoke end clearance... when the carrier moves, so does the pinion shaft. There has to be some clearance to allow carrier adjustment without causing yoke bind.
This is why there is no published spec for this... as the carrier is adjusted, the yoke clearance will change. Some guys add metal to the yokes to get near zero endplay, some guys run without the clips .... this is one of those "gray" areas.
[Modified by Tom454, 7:16 AM 2/14/2002]
Melting Slicks
Joined: Dec 2000
Posts: 2,635
Likes: 0
From: Union Ontario
Re: Need differential help! (Tom454)
Tom,
Norval and I have had some discussions on running without the side clips on the yokes. What are the benefits and/or side effects of running without them. I can see that you would lose the effect of the halfshaft being your upper control arm(this would affect camber change through suspension travel) but is there anything else? I think the suspension would feel more loose than with the clips installed.
Norval and I have had some discussions on running without the side clips on the yokes. What are the benefits and/or side effects of running without them. I can see that you would lose the effect of the halfshaft being your upper control arm(this would affect camber change through suspension travel) but is there anything else? I think the suspension would feel more loose than with the clips installed.
Thread Starter
Race Director
Joined: Dec 1999
Posts: 16,945
Likes: 9
Re: Need differential help! (Tom454)
My buddies pinion shaft looks a-okay unlike mine did when I had it apart. Mine was all blue/purple and pretty burred, installed a new one and all is fine. I guess some moron pre owner didn't fill it up with enough fluid
Marck
Marck
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
Re: Need differential help! (MikeC)
Without a upper strut rod or 6 link you can not run without the clips. If you run a 6 link and run clips the suspension will bind. Lying under the car with the 6 link installed , the 1/2 shafts in place and no clips and moving the suspension through it's full travel you should see how much the yoke moves in and out of the rearend. Probably 1/4 inch. If the clips were still in place with the upper strut rod the whole thing would go into bind.
Using a magnetic protractor the protractor stays to zero. I never tried this with the half shaft and clips installed and no upper strut rod. It would be interesting to see how much it changed. Using the 1/2 shaft as a upper rod it would have to change alot.
If this clip would fail while in operation wouldn't the wheel flop over in the wheel well? Also if you have 1/10 of an inch play at the center of the wheel and the bottom of the wheel fixed with a strut rod wouldn't the top of the wheel have alot of play?
The wheel would pivot around the lower strut rod and because of the distance to the top of the wheel this 1/10 would magnify it's self considerably.
Using a magnetic protractor the protractor stays to zero. I never tried this with the half shaft and clips installed and no upper strut rod. It would be interesting to see how much it changed. Using the 1/2 shaft as a upper rod it would have to change alot.
If this clip would fail while in operation wouldn't the wheel flop over in the wheel well? Also if you have 1/10 of an inch play at the center of the wheel and the bottom of the wheel fixed with a strut rod wouldn't the top of the wheel have alot of play?
The wheel would pivot around the lower strut rod and because of the distance to the top of the wheel this 1/10 would magnify it's self considerably.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
Racer
Joined: Sep 2001
Posts: 354
Likes: 0
From: Prineville Oregon
Re: Need differential help! (Tom454)
Don't forget that your C-clips rest against the side of your large spider gears...your large spider gears in turn rest or push against the sides of your posi-clutch pack, as the clutches wear you will have more clearance to take up...which you'll see in the end play of your side axle yoke.
Normally one would not run without the C-clip unless they had installed a six-link set-up on the rear-end, otherwise there would be nothing to hold the axle in place. This would allow the swing-arm to move sideways and you'd lose your alignment...infact the top of the tire could move out far enough to hit the body. Deen :eek:
Normally one would not run without the C-clip unless they had installed a six-link set-up on the rear-end, otherwise there would be nothing to hold the axle in place. This would allow the swing-arm to move sideways and you'd lose your alignment...infact the top of the tire could move out far enough to hit the body. Deen :eek:
Le Mans Master
Joined: Apr 1999
Posts: 6,134
Likes: 46
From: Raleigh North Carolina
Re: Need differential help! (norvalwilhelm)
I tend to favor using the clips... but as we will probably see when everyone wakes up and gets on the forum today.... there will be a pi$$ing contest on this issue. So I'm staying out of it. :)
Melting Slicks
Joined: Dec 2000
Posts: 2,635
Likes: 0
From: Union Ontario
Re: Need differential help! (Tom454)
Norval, I'm not trying to **** you off, I just want to find out if you can run without clips, as per our email discussion from a few weeks back. I am not suggesting running without them, I know it will screw up the alignment on the car. I also know it is not suggested to run without them, I am just wondering about what these people think the benefits are, I see it as a detriment to run without them. AS I said before I might be running without one on one side due to the wear on the end of the yoke.
Come visit me this summer and we'll run an experiment with my car, we'll pull the clips and check the aligment(camber change versus suspension travel) take it out for a ride and check it out that way.
I'm not against you Norval, I'm with you, I am just trying to find out how bad it is to run without a c-clip since I might possibly be in that situation.
Come visit me this summer and we'll run an experiment with my car, we'll pull the clips and check the aligment(camber change versus suspension travel) take it out for a ride and check it out that way.
I'm not against you Norval, I'm with you, I am just trying to find out how bad it is to run without a c-clip since I might possibly be in that situation.
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
Re: Need differential help! (MikeC)
Without a six link you can NOT run without c clips. Nothing would be holding the 1/2 shaft on. The top of the tire would flop out into the body work.
As for running with clips on a 6 link ? This would not work for now the 1/2 shafts want to move in and out as the suspension moves. The upper strut rod now controls the movement of the top of the wheel. I could easily prove this lying under my car with the 6 link installed and watch the 1/2 shaft moving in and out as the suspension is moved through it's travel.
I ground the ends off my yokes right back to the grove to prevent any binding in the suspension.
As for running with clips on a 6 link ? This would not work for now the 1/2 shafts want to move in and out as the suspension moves. The upper strut rod now controls the movement of the top of the wheel. I could easily prove this lying under my car with the 6 link installed and watch the 1/2 shaft moving in and out as the suspension is moved through it's travel.
I ground the ends off my yokes right back to the grove to prevent any binding in the suspension.
Melting Slicks
Joined: Dec 2000
Posts: 2,635
Likes: 0
From: Union Ontario
Re: Need differential help! (norvalwilhelm)
You got me there Norval, during extreme suspension compression the wheels would flop out possibly onto the body work.
As for the 6 link, of course you couldn't run with the clips installed, the suspension would bind during travel, possibly causing some very expensive parts to break.
I still say we test this theory out this summer, compare the stock suspension, stock without clips, and your 6 link, and post the results.
As for the 6 link, of course you couldn't run with the clips installed, the suspension would bind during travel, possibly causing some very expensive parts to break.
I still say we test this theory out this summer, compare the stock suspension, stock without clips, and your 6 link, and post the results.