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07-30-2005, 06:05 PM #1
Never done this before fellas.
I've been told that there are three U-Joints in my 2002 extended cab Sierra 1500 2WD.
They are cheap ($9 each), and I have been told by some that they can be beat off with a hammer, and others have told me a press is needed.
I have also been told that I need to back the truck up on ramps, in order to incline the truck with the nose (engine) down, in order to keep the transmission fluid from pouring out.
Others have told me the tranny fluid will not pour out even if on level ground.
Some have also told me stories of some type of needle bearings involved, that have to be "re-aligned" ??
Bottom line is some say it's a piece of cake, others say it's hell.
I tend to believe it's very doable, but thought I'd see what you guys have to say.
I'm mainly concerned with whether or not a press is needed for this job...?
As always, thanks fellas...
07-30-2005, 06:16 PM #2
Hey Paul, Whats up with a 2002 model needing joints anyway? Can it be done without a press? probably. Should you use a press? probably. Got a Autozone near you? They may have a portable one for a loaner. OTC and others make pullers for em too. When you pull the trans drive shaft out fluid will follow. Now I have used a good vise with sockets to press em out. That is a good way to wreck a vise though. Im suggesting borrow or go to a friend with a press to get the joints apart. One good hammer blow in the wrong place and make your job a whole lot tougher IMHO. Good luck
07-30-2005, 06:20 PM #3
I used a big vise 'cause I had no press. It was a long time ago... I think I used I socket in the vise to drive the u-joint out.. Sould be a piece of cake. Putting the rear of the truck up can't hurt though I don't think to much tranny juice will leak out............
07-30-2005, 06:42 PM #4
For a few bucks you can get a plastic plug to keep the oil in the tranny while the driveshaft is out. I think the re-align you ask about is for two piece shafts. To reduce vibration, you need to maintain the clock position of the u-joints the same as they were before you disassembled it. Most tool rental places around here rent the OTC C-press tool, really speeds up the process. I don't know what year GM stopped using plastic to retain the joints, if you don't see clips look for a small hole with plastic oozing out of it. You'll have to heat things enough to soften the plastic before pressing. Replacement joints will come with clips.
07-30-2005, 06:56 PM #5
You will lose very little fluid when you slip the yoke out of the trans, even on level ground. Its a whole lot simpler to put a pan under there to catch what little bit does leak out than to mess with the ramp thing.
If GM continued to assemble these joints like they did in the first half of the 90's, the cups will be retained in the yokes by a ring of hotmelt adhesive. Trying to press these apart is about impossible. First time I replaced mine I fooled with them for an hour trying to figure out why they wouldnt come apart and how they stayed in place since they had no circlips or retaining rings on the cups. Finally decided they must be rusted to hell so I put some heat on the yoke with a torch to free the "rust". Once the joint got warm, this goo starts squirting out thru a hole that was drilled into the eye of the yoke. Kept heating till no more of the stuff was coming out, did the same at the other eyes, and the cups then pushed out easily using a vise and a socket. The replacement joints come with circlips which install in a groove at the inner end of each cup once the joint is assembled. Once the driveshaft is out, if there is no retaining clip at either the inner or outer end of each cup, then that would be an indication that they still use the hotmelt for production assembly. It doesn't take a lot of heat to get the glue to release, but heating works much better than attempting to use a big press and shear the ring of glue, since that can result in pushing one of the ears of the yoke out of line. When that happens its real tough to ever get the yoke eyes properly aligned again.
If this is a job you haven't done before, I'd recommend you enlist a friend who has done it before. You can do the grunt work and let him supervise and point out the pitfalls like getting one roller crosswise in the bottom of a cup, etc. Its not a hard job, but its one thats much more likely to be successful on the first try if there's someone handy who knows the things that can (and will) often go wrong.
07-30-2005, 06:56 PM #6
Smyyt58 pretty much has all the straight stuff in his post. I can say though that if you let just one of those needle bearings drop out of place it won't allow the cross to go all the way back into the cup and you have a mess if you don't find it till you start to insert the opposite cup and things won't go all the way back together. Valvoline makes a black, really sticky grease, comes in a 1 lb can, that will help hold the needles in place for the assembly.
A press? Hell, I thought I was sh@tting in high cotton when I finally got a vise big enough and strong enough to use, still have an 8 oz ball peen hammer that has a flat on the end of the ball from hammering on the end of it while using it as a driver to insert cups of U-joints rolleyes:
07-30-2005, 07:09 PM #7
You should be able to take the whole drive shaft off without effecting the transmission or rear end. If you unbolt the yoke from the rearend you just pull it off of the transmission as it is splined at that end. I used a paint pen and marked the the rearend,transmission, and on each knuckle to makes sure it went back as it was before.
I would not recommend hammering or using a press to shove out the cups. If you cannot see horseshoe clips they are likely original the joint cups are held in a plastic goog from factory.
Use your vise with a larger spacer to push the cup through and the otherside of the yoke a socket or something slightly smaller then the cup pinching this arrangement into the vise. Take a torch and heat the ends of the yokes where the cups are real good and the plastic goop should start oozing out of the injection holes. Crank the vise handle and they should come out fairly easy. Having a third hand helps [img]smile.gif[/img] . While you have it a part you can also buy a special grease to lub the constant velocity joint as there is no grease nipple there.
07-30-2005, 07:14 PM #8
must have been typing while you guys were talking so forgive the double post advice.
07-30-2005, 11:26 PM #9
I am not sure why it is hard to believe that an 02 needs U Joints.
I have 100K on the truck already. Lots of driving to different jobs in the contracting business.
I thought at 100K miles, one should replace the U joints, especially when you hear them making a clanging noise. There are no grease fittings on the factory U Joints either. (not sure why this is????)
Not sure what this means:
"While you have it a part you can also buy a special grease to lub the constant velocity joint as there is no grease nipple there.".
-Is this "velocity joint" the same as a midshaft bearing?
Excuse the ignorance, but I've never worked on autos much, mostly due to lack of time.
I spoke with my buddy who drives a 2002 GMC 3500 Dually. He said his U Joints did indeed have the plastic inside, that had to be heated with a torch. He did it just the other day in fact.
This leads me to believe that mine are probably the exact same.
07-30-2005, 11:39 PM #10
Because my Chevy 3/4 ton has 325K with original U Joints. If you have a bad U joint you should be able to get some movement in the bearings of the joints. A noise is sometimes a loose bolt(s) in the drive train or driveshaft bearing hanger or similar can be making the noise. Id be pushing and pulling on the U joints and inspecting everything first.
07-31-2005, 12:37 AM #11
I've changed them a couple times on my S-10, 175K.
The original motivation was a wierd and very pronounced shudder I got at 45mph as the torque converter was locking up around 60K when I bought it. The OEM ones from Michigan service had one of the cups full of "rust and dust"....there wasn't a single needle in there but it merrily carried me to Texas and back before I realized what was up.
I made the (in hindsight) mistake of using that red grease...Mobil 1, that all the oil ran out of sitting on the shelf. That lunched set #2 in my thinking...wore a "chatter" pattern into the trunnion surface in short order.
I finally chucked the sorry red grease and set #3 has been going strong on regular #2 grease, I think it's Mobil XHP222 with some moly disulfide added.
I use a paint marker to draw a line on opposing joints to keep the clocking straight....the x-cab S-10 has an intermediate driveshaft, so an extra set of U-joints are in there plus a center bearing support. I tried a sharpie but that got so greasy from handling the thing that it was all but erased.
07-31-2005, 04:03 AM #12
Before you start the job chock the wheels so the vehicle can't roll. Once you remove the drive shaft park or a gear won't do anything the stop it from rolling. You probably already know this but I thought it was worth mentioning.
The rest has been covered pretty well. Good luck.
07-31-2005, 04:53 AM #13
I am not sure if your truck has a constant velocity joint, but my Sonoma xcab does. Below is link to what it looks like (figure 5) on that site. In my case when I went from reverse to forward I got a clunk sound. The drive line was solid with no slop. The rear cross was seized.
After you set the crosses back into the yoke they may flex rather stiffly especially if you had a hard time pressing out the old cups. Take a hammer and punch and give each ear on the end lip of the yoke a good sharp rap from the inside out.
07-31-2005, 10:21 AM #14
"There are no grease fittings on the factory U Joints either. (not sure why this is????)"
This is so GM can save 2 cents on every $40,000.00 truck they sell.
07-31-2005, 11:02 AM #15
usually when you need new u- joints it is most noticable when you take it from part to rev to d1. you should hear a clunck noise.. to remove it is best in a press with a little heat. i have beaten these things out with no heat. becarful not to hit the drive shaft or it will vibrate.
08-01-2005, 12:52 AM #16
to mark the mating u-joint parts, i grab a center punch, & mark a dot on the opposing parts. on the second u-joint i mark with 2 dots. it is grease proof, but hard to see.
08-01-2005, 01:37 AM #17
easy to do, use a large c-clamp, and a couple sockets, one larger and one smaller than then the bearing caps, pull the clips and the grease fitting then press the joint out.
Best way to see if the joint is bad is to park the truck on level ground, (block wheels) then put it in nuetral, and with it shut off, climb under and try to turn the driveshaft back and forth if the joint's bad it will show play
Using the c-clamp and sockets is what I do when I'm offroading and break a u-joint, it can be done easily under the truck
when you reassemble the joint, place the cross in the yoke as it should be, so one end sticks out as far as possible, slip the cap on that end, then press it through, use small socket to press the other side into the large socket, far enough so you have the other end of the cross sticking out as far as you can WITHOUT pushing the cap into the inside of the yoke, then place the other cap on the cross, press it in till you cam put the clips and grease fitting in, that way you don't have to worry so much about tweaking the needles
Easy, I've done it in 10 minutes laying in mud