Half-shafts again, I think

[Don W.]

Well in my other thread you saw that everything pointed to the transfer case being the culprit. Swap the TC, everything works, go to the track and there is a single knock, like a hammer on the 1-2 shift. Couple of runs later passing about 80 it sounds like a 50cal machine-gun going off inside the cab. Will be taking another look at my half-shafts tomorrow. At least they are easier to change than the TC.

Just thinking out loud I wonder if the new TC is now sending the correct torque to the front which, in turn, grenaded the half-shafts. At least the right one.

 

[TYTILIDIE]

Re: Half-shafts again, I think

They were already trashed. When that stress is put on them the damage is done.

 

[Don W.]

Re: Half-shafts again, I think

OK, I don't have the half shafts out but wheels off looking at half shafts and they -look- fine. Turn one and the other turns the other way (because of the dif, of course) just smooth as can be. No evidence of damage, no binding. Boots are clean and unbroken. Put a pry bar up against them and there's no slop.

I don't get it. Something is making a awful racket at speeds of, say, 80. Tends to go away as I slow down. Could the half-shafts be that bad and show no evidence?

I guess I'll go ahead an pull 'em so I can have them in my hand but I'm sure open for ideas.

Could a blown trans drive normal and sound like someone dumped a bunch of rocks into it then go away when I slow down? Or, for that matter, a transfer case?

Sign me frustrated right now...

EDIT: I've posted a question for George Blake over on his trans "sticky." thread. Thinking I may have done something inside the trans.

 

[WyoSyclone]

Re: Half-shafts again, I think

Hi Don, I can't remember.. did you change your spindle bearings... I think they're a roller bearing. If one roller is bad and temporarily freezing up or trying to override the next roller it will make that sound. You should hear somewhat of a droning sound as you push on the gas and let off.

 

[Don W.]

Re: Half-shafts again, I think

Don't think it's spindle bearings. Everything is quiet until about 80 then all hell breaks loose. I think it's the trans. based on this comment by George Blake:

"When you shifted it into neutral, the sprag and the input drum take a engine rpmX2.5 increase so it goes from 2100 to 5250 instantly. This can balloon the reverse drum and the sun gear shell because there is NO load. If you do that at 3000 rpm you get an instant 7500 rpm increase in transmission internal components. You will break something doing that. It will just take ONE time."

I'm gonna take the truck to my trans shop and have him look at it.

 

[TYTILIDIE]

Re: Half-shafts again, I think

Don, does the truck shake really bad when you hear this noise? If so, its your CV's man. I have had this problem 4 times in the last 8 months. 2 of the times it was just a flat out explosion. First time it happened I was doing about 100 on my way up to Denver in the middle of the night to pick a friend up form the airport. Scared the living shit of me. Funny thing is that at 70mph on the nose it would do it. It wasn't gradual either, just started acting crazy. After doing my viscous, I changed out both shafts and thoroughly inspected both wheel bearings. The best way to do it is with the tire on, try and move the tire up and down, if it moves, thats it. If you want to take them off, you can spin them and see what they spin like. Should be real smooth. I have had a few that wobble or vibrate when you spin them in your hand.

 

[Don W.]

Re: Half-shafts again, I think

Thanks Mike,

Right this minute I'm just upset, to put it mildly, at the truck. Like I said, to look at the shafts they look fine. Pry-bar on the center section and there's no movement. everything turns smooth. George Blake suggested I go for a test run with the trans in OD then again is D and see what happens. It just occurred to me that I should put the suspension up to it's "normal" position instead of extended like it is now and see what happens. I think I'll try that first then pull the pas shaft, where the noise seems to come from, and see how it is when it's in my hands.

 

[WyoSyclone]

Re: Half-shafts again, I think

I had a CV joint go out once on a VW.... sounded exactly like a rod knocking... happened on vacation and actually pulled the pan off and checked the rod bearings. Turned out it was the passenger side CV right next to the exhaust downpipe.....felt perfect, but man what a noise it made!

 

[George Blake]

Re: Half-shafts again, I think

Yeah, OD vs D will rule out an internal component/rpm issue with the Trans or engine. If it does it at the same road speed, then you KNOW it is a road speed sensitive component(CV axle, prop, rear driveshaft).

Now one of the guys kept going through the passenger side CV axle popping loose from the tube on the pass side. There is a snap ring that kinda holds it in there. He'd replace the snap ring and it'd pop right back out again. He was from Ky. Jeff Scott and Mike Hardman knew him. I forget what he went by on here, but he may be able to shed some light if yours sounds like his did when his did that.

Thanks Mike,

Right this minute I'm just upset, to put it mildly, at the truck. Like I said, to look at the shafts they look fine. Pry-bar on the center section and there's no movement. everything turns smooth. George Blake suggested I go for a test run with the trans in OD then again is D and see what happens. It just occurred to me that I should put the suspension up to it's "normal" position instead of extended like it is now and see what happens. I think I'll try that first then pull the pas shaft, where the noise seems to come from, and see how it is when it's in my hands.

 

[Don W.]

Re: Half-shafts again, I think

As I write this it's started to rain so I'm here. May, repeat may, have found the trouble. I can push the drivers side half-shaft in flush with the hub by hand. Pas side nada. Goes a just a little and stops. Quite a bit of pressure with a puller and it only went a bit further. I'm told I can cut the rubber and there's a "C" clip of some kind in there which will allow me to disassemble the half-shaft to get it out. Might be Thursday before it's out 'tween appointments and racing tomorrow (with the Tailblazer) I'll be optimistic here and say I'll post a pic. later.

 

[Don W.]

Re: Half-shafts again, I think

Two brand new half-shafts sitting in my garage. We'll see if I can get them in tomorrow. Raining outside right now but supposed to quit by morning. I'll let you know what I paid. Haven't got the bill yet.

 

[TYTILIDIE]

Re: Half-shafts again, I think

I got mine at NAPA new for $125. So far so good. Dealer wanted $675 a piece, a bit much IMO. I'ld bet my box of Lucky Charms in the cupboard this is your problem. Like I said before, had it happen several times and I know what its like, NOT GOOD!! I think the passenger side makes all the racket because its the main drive axle for the front, is it not? I'm pretty sure it has something to do with that. Passenger side is the one I kept having trouble with as well.

 

[Don W.]

Re: Half-shafts again, I think

Well pas side is out. What a total PITA for something that looks so simple. I could not get it out until I gave up and completely removed the drag-link assembly and tied the (gas) shock well up out of the way. Even then the outer boot went up against the shock mount.

Wheels bearing seems OK but the seal is leaking a bit so I think I'll change both while I'm at it. With the bearing out of the way hopefully install will be a bit easier. If anybody has the part # for the non ABS Timken bearing handy I'd appreciate it.

 

[Don W.]

Re: Half-shafts again, I think

Thanks!

 

[WyoSyclone]

Re: Half-shafts again, I think

Hey Don, I'm all out of opcorn:



Did you solve this problem??

 

[Don W.]

Re: Half-shafts again, I think

Got a little carried away. Decided to do the lower ball joints while I had everything apart.