GATOR454

I am replacing my stock suspension with a performance suspension from VBP. While I have the drive and half shafts out I am going to replace the U-joints. Is it worth the extra cost to get the U-joints with grease fittings? Are there any cons to getting greasable U-joints?

Thanks,
David

Fevre

The zerk is a stress point that can crack, go with spicer solids.

Twin_Turbo

:iagree: and the brute force things have sharp angles where the machined trunions meat up to the centers which is a stress point too. Solid spicers are the oinly way to go.

mayberg

I saw some u-joints - I think they were Spicers - that had the grease zerk in the cap - not in the intersection of the +. That looked pretty strong to me.

rob75383

I've currently got a full set of zerk'd u-joints. I've also got a pronounced clunk when going into drive/reverse. I can't say for sure if its the u-joints themselves, but to be on the safe side, I'm gonna get me a full set of spicers to replace the one I've got.
...just want to mention something: you might want to check your spindle flange extra carefully when redoing your rear end. Both of mine had warped over the years, and I was completely unable to put the u-joints in at home. I had my machine shop do it, but they said it was a PITA. They had to use a hyd. press, along with a vise to straighten out the flanges. I'm betting that that's where my mystery noise comes from... warped spindle flanges. Just a warning.

Besides, by your userid, GATOR454, I can see you've got some serious tq potential with a BB under the hood, and the solid spicers would be the way to go.

Apeiron

Greasble U-joints are adequately strong if they're installed with the zerk under compression with normal rotation, not under tension.

rob75383

I agree with your statement, and I run the zerk'd one with no problems (besides the mystery noise, but that could be almost anything), but... I'm personally not willing to risk a failure of one the u-joints on the half-shafts, or the driveshaft.
Did you see the pics that someone posted about a year ago, when they lost a u-joint on one of the halfshafts??
Its a little more investment in a crutial part, for a little extra protection.

The flipside is: I bet even the solid spicers let go once in while :eek: , although probably under major torque.

ZD75blue

IF you drive like a grandma... then anything would work...

But if you ever power break, drop the clutch etc... my understanding is to go spicer solid... !!!!

RJR99SS

i run solid brute forces in my vette.

I do know for a fact that in most cars, greasable u-joints are just flat out worthless. The reason being, is that the yolks gets in the way of actually greasing it, you cant even fit the grease tip in there.

All you can do is remove the driveshaft from the rear end and move it around until you can get the grease fitting in there.

GATOR454

Does anyone know the correct Spicer part #?
Also, where can you get them?

Crickett

:iagree:

Crickett

That clunk is from the differential I'd bet. Mine does the same thing. You just need to buy a new diff bushing. You can buy one at VBP. Here's the link. http://www.vettebrakes.com/ :thumbs:

mapman

:iagree:

.

72GACRZR

Don't bet too much. I have a clunk and replaced a shot front bushing, but the clunk is still there and getting worst. Going after U-joints next and then to rear end.

GTR1999

The current spicer numbers for the 75 I just did are
5-799x for the 1/2 shaft
5-790x for the driveshaft they're about $18-$20 each.
Gary

Garrett1972

I am a newbee here, but I do remember an article that I read a while ago in a 4 wheel drive magazine. They tested U-joints in a special fixture designed to tear them apart. the results were that as long as the Zerk fitting was in compression, there was no difference in strength from a solid U-joint. :seeya

Fevre

Jack one rear wheel off the ground and see if you have any front back play in it. I found my rear end clunk in my Formula is about a 1/4 to 1/2 play in the posi, I can move one wheel back forth that much and it make the clunk sounds. The 2 u-joints are tight as well as the tranny.

rob75383

Cricket: I thought the same thing last year. I had set of rubber mounts on the whole drivetrain. The motor mounts kept wiping out, so I bought a full set of polys, engine, trans, and diff. The rubber diff bushing was vitually perfect, but I switched to poly to match the rest of the mounts.

Ferve: Front-Back play??? Do you mean pulling the tire towards you, and pushing it back in to see how much play there is??
Or do you mean ROLLING the tire forward and backward to see how much play there is between the ring and pinion??

I know there is a slight amount of play, when rolling it forward and backward. I checked that last year, but it was only like a 16th of an inch. I too am going to replace the u-joints (along with the spindle flanges), and then from there I'll pull the diff again.
Maybe I just need to put in a new set of shims and a new crush sleeve??

--my apologies for hijacking the thread :bb