in2pro

My next fun project as soon as it warms up...
My 2007 Tahoe has a little over 100k miles now and I was getting the "clunk" from the dry spline on the slip yoke... I pulled the drive shaft and greased the splines up and boy what a difference!
While I had the shaft out I checked the movement of the u-joints, the front felt smooth and somewhat easy to move but the rear felt a bit stiff...
I like preventative maintenance so I'll tackle this project soon and post a few pictures of my adventure

Till then please chime in with your tips & tricks or experiences replacing u-joints

73shark

If you don't have a press, you can use a big vise and a couple of sockets that are the right size. One that's big enuf to allow a bearing inside and another one that's small enuf to fit inside the opposite side so you can press the bearing out. Then switch sides and press the other side out. Rinse and repeat for the other pair. Hope this makes sense cuz it's been awhile since I've done it. Once the kids left the nest, I don't have to do much wrenching any more.

Have you checked youtube?

SabrToothSqrl

I'm getting a good clunk when accelerating from a deceleration. I also suspect the slip yoke. shame it's 20 degrees out, else I'd get right on that.

Looks like I'll do it this spring.

in2pro

The slip yoke was a breeze to grease, just be sure to use the correct type of lubricant called out by GM to be compatible with the transmission fluid...
take off the 2 brackets are the rear differential slid the drive shaft forward enough to clear, lower is a bit and slide it out, I'd hold onto the slip yoke to prevent it from hitting the ground...
*CHOCK YOUR WHEELS* before you start.

I have to wait till it warms and drys up here before I will get on the ground...

SabrToothSqrl

good call on the grease- i was just going to use my normal go to marine grease.

I've seen youtubes on greasing the slip yoke, so I'll check back in spring.

The heated garage is nice, but the floor is cold... I only keep it at 40, and I'm not turning it up just for this fix...

I do have a nice creeper though... hmmm... I'm bored in winter, but not that bored lol.

in2pro

Here is the stuff that is called out and what I used, but there are probably equivalents available

Genuine GM Fluid 19257121 High Temperature slip yoke grease

in2pro

Harbor Fright has a 1 ton arbor press for ~$40.... sounds like a good reason to buy a new tool I am sure the wife will understand that I have to have it...

73shark

I picked up Harbor Freight's 12 ton hydraulic press a couple of years ago for about $90 after the sale price and coupons.

in2pro

I got the u-joints both front and rear knocked out this week and also changed the differential fluid as well...
The new ones are grease-able too.
The old ones were still solid but the grease in them was turning black so they had lots of wear.
TIPS for U-joints..

Start with the slip yoke side so that you are not flopping it around when doing the tail end

Use MAP gas to melt the nylon injection ring, and it takes a bit of heating so take the time to heat and then the caps will push out much easier, but make no mistake they still take some effort, a second pair of hands is very helpful.

Wear gloves, that shick gets hot!

I used an arbor press to get the old ones out, but you can pound them out using a socket of the correct size as 73shark suggested above, as I tried both methods..
Take your time putting new ones in, the caps tend to slip off, you don't want needle bearings getting loose or wayward..

The grease zerks need to point toward the center of the drive shaft at both ends... trust me I know now...

Grease the slip yoke before you put install it to address any clunks, if you don't have them (clunks) grease it anyway...

It took a bit more effort then I expected to get the new caps seated so the retaining rings would clip in, this left the joints tight in my opinion so I will regularly monitor them for the next few months...
remember to grease them once you are done, and i would hit them again after a couple of hundred miles and they should be good until next chassis lube..

TIPS for differential fluid change.

Jack that end up high unless you have a lift, I was able to sit somewhat comfortably under the truck once the spare was out of the way...

It was time for a change, the old stuff was honey brown, the new stuff ( Mobil 1 75w-90 synthetic) was considerably lighter in color..

BUY the gasket, you may hear that the gasket in place is reusable but it won't be if your vehicle is more then a year or two old.. and you shouldn't count on it being usable even then, replace it.

Cover the gears with paper towels or plastic while you scrap off the old gasket, sure you are likely to clean the assembly with brake cleaner but there is no point risking getting contaminates inside if you don't have too so it will be less to clean out and worry about...

Take the time to get both mating surfaces clean, do it right the first time as its messy and that gear oil stinks...

Don't rush the job, let the cleaner have time to evaporate, give any gasket sealant the proper time to set before tightening, and I'd give it another 10-15 minutes after torquing before filling, (I used the time to put tools away)

Torque the bolts to 40 N.m (30 lb ft). I used a crisscross pattern after getting all bolts 1/2 turn tight.

I was able to get 2 of the quart bottles in with the vehicle up on jack stands and then put in the last half or so of the last quart with the vehicle on level ground to top it off to fill level of 0-13mm below fill port....

I did use a bottle pump attachment to get the last bottle in, that $4 was worth it to keep it clean and controlled on the topping off....


Tighten the drain plug to 33 N.m (24 lb in).







.

73shark

And for greaseable U-joints, one should install such that the zerk hole is in compression when the vehicle is going forward. This mitigates the potential weakness caused by the hole.