R. Bruno

I have begun a rear suspension rebuild and notice that the passenger side yoke has 1/2 inch play when I do the "12 and 6" test with the tire. The rearend has not given me any trouble but I know this is something that I should fix while I'm in there. Should I send the whole unit off to Bairs for a complete rebuild or are there other options I might consider? Any advice is appreciated.

Smokehouse69

If you are seeing 1/2" of movement (in/out) of your yoke, then you have a problem and probably need to replace the yokes. The actual replacement isn't hard, but dropping the pumpkin can be a royal PITA on pre-1980 cars.
Your yokes might be worn enough that the ends might be mushroomed out and the retaining clips completely gone.
I did the job last spring with the support of people on this forum. In my case the wear wasn't bad and the yokes were easy to slide out of the pumpkin. I bought two replacement yokes, and new seals did the install in about 30 minutes. The 30 minutes was preceded by several hours of work it took to drop the pumpkin and crossmember.

GTR1999

1/2"(.500") is way too much. Like Steve said the yokes are probably shot. If the rear is running ok and you really don't want to drop it I would disconnect the 1/2 shafts from the rear yokes and use an indicator to check the actual movement in and out. It sometimes can be tricky trying to measure the play with everything connected. If you still have .500 then I would say it's time to drop the rear and fix it. I have a rear apart now that I'm going through and they don't seem too bad,but you need some good measurement tools. You might be able to get away with replacing the yokes anf flushing out the housing good then adding new posi additive and lube. Check for metal in the old oil when you drain it.
Good Luck,
Gary

mrvette

When you have all that much side yoke wear, that metal went somewhere, that means shot carrier (ring gear assy) bearings and probably the small front pinion bearing shot too.....strangely enough the large bearing behind the pinion head sometimes survives.....at any rate, a complete tear down and o'haul is needed....do a posi clutch pack if any of the plates are worn smooth...

GENE

MIKER

Check out the prices for inner yoke shafts (stub axles) at Corvette Parts Man.com www.corvettepartsman.com

They are as low as $63 for refurbished ones and $75 for new ones.

R. Bruno

Thanks guys. I will drop the rear and most likely just send it off. I wanted to get a reality check before spending the $500+ yokes at Bairs but it seems like this is both the easiest and surest way of getting it fixed right.

jvm

I have the same problem. I guess it depends how much you like being under the car. All my bushings, shocks, yokes were shot. I decided to do the whole thing and be done with it. I replaced all U-joints also. Bairs was recommened to do the T/As work so There they went. I never had repair people call me to tell me they came in and were going to get right on them. Gave a me a turnaround date. Called me again and told what was going on my credit card. Nice people!!!

From what I have been following on the forum 79s were a hit or miss when it came to having correctly tempered yokes. Jim

GTR1999

If you're going to send it out then Bair's would be my first choice. Their work has been well documents here since this forum began.

R. Bruno

Thanks again. I have read the many threads about Bairs and they seem to be very good.

Barry's70LT1

Are you measuring the 1/2" at the top of the tire, or the "actual" movement
"in/out" of the yoke itself.????????
If the 1/2" is at the tire, then you have wheel bearing play plus yoke movement combined, exaggerated over the distance of the tire.
What appears excessive, might be within tolerance.

Barry

R. Bruno

Barry - Thanks for the answer. The movement is approximately 1/2" at the top of the tire on the passenger side , but I can see the yoke moving out when I pull. The drivers side has no movement when I do the same. I am going to pull the wheels, spring, struts and halfshafts this weekend and measure the movement at the yoke. Do you know how much movement at the yoke is tolerable?

GTR1999

I was told( here I think) that .080" was about it, over that and it's worn. I don't think there's published dimension of end play for the firat design C2 & C3 yokes though. For a comparision my 55k mile 72 has .044" and .045" play in it. Alignment and usage I think would play a factor in the life of the yoke. I'm planning on having the ends welded and fitting them to about .010 -.020" end play. First though check the movement like I said without anything connected to the yokes, you may be surprised at what you find. Good Luck
Gary

R. Bruno

gtr1999- Thanks. I will check this weekend, but based on the in and out movement I can see, sounds like time for a rebuild.