The plastic seal is sort of a new thing.
They were new in the mid-1970s, maybe.
My friend whos a ASE, GM Tech and works at a GMC dealership said that he would never want to replace Ujoints on my trailblazer because you literally have to get the real deal cutting torch that uses ACELYTE or something like that with an oxygen mix that u could cut steel with and get the ujoint glowing red and then bang the **** out of it with a hammer till it comes loose
Which proves that ASE certification does not weed out ALL the idiots, just most of them.
i have a 08 trailblazer lt what is the strap on the u joint from side to side
If it's the strap I'm thinking of, it holds the caps in place during assembly into the rear axle pinion yoke, so the caps don't fall off. Once the shaft is installed, that strap serves no purpose.
My 03 has 205K miles, for the last few thousand there's been vibration in the seat (but not in the steering wheel) at highway speed. There was a hint of vibration at 53 mph that went away by 55, then it came back at 68 and got worse with speed so that at 75 the rear view mirror was unusable because the mirror shook so bad I couldn't make out the image.
Wanting to not deal with this in my driveway at below-freezing temps, I drove to a shop and had them diagnose the problem. They had the vehicle two days, could not say for sure where the vibration was originating. When on the lift with the engine revved-up and in gear, the rear axle assembly shook, but the transfer case was smooth.
The wheels were balanced (no change) and they played games with the driveshaft balance using hose-clamps as repositionable weights, (no change). I took the Trailblazer home and put on my cold-weather gear. Four 7/16-hex-head bolts removed, driveshaft popped forward with a nudge from a prybar, then removed, and off to the local welding/machine shop with the shaft.
Three hours later, I get a call. They've replaced the two U-joints (front joint looked good, rear joint looked terrible. It's fairly common for the rear joint to fail before the front joint.) They put all drive shafts on a lathe, where they found that the shaft was bent about 0.040, they said they managed to straighten most of the bend back out. They found that the shaft was closer to balanced without the stock weight at the rear. They welded new weights front and rear to make it as good as possible. $100 for their labor, $21 for parts, I greased the splines, emery-clothed the rust from the rear-axle pinion yoke and straps, anti-seized the bolts, and gave it some loving torque to the fasteners.
Trailblazer is now totally smooth at 90 mph, in fact the truck is smoother now at ALL speeds, even though I hadn't noticed a problem with lower-speed vibration until it wasn't there any more.
Total Success!
I hauled the beat-up U-joint back to the shop so they could have a Teachable Moment.