changed out prop shaft, now what?

[ogwutang]

97 XLT AWD 5.0. prop shaft was poppin so i bought a new one. installed it and it still popped, so i took it back and they said it was for a 98, not a 97. (they looked the same to me). so they looked it up and i had to send off my core to be rebuilt, so i did. this whole time the truck did not pop without the prop shaft in. i just got it back and reinstalled it, and now its popping again. WTF? transfer case? front diff? i haven't a clue :

 

[yavapaires]

Try jacking it up, and see where the noise is coming from. Just spin the front wheels by hand, see if you get a noise. If not, you'll have to put it in gear and apply power to see where you are getting the noise BE SURE TO SET THE PARKING BRAKE!. or better yet, if you can, get all four wheels off the ground.

 

[ogwutang]

i've put the front in the air and spun the front wheels, because i was hoping maybe it was a front cv joint, but no dice. it spun nice and quiet. i didnt think it was the front cv's because it only pops when i drive straight. when it turns left or right the popping stops. i might put the whole truck in the air and let it idle in gear and hopefully i can narrow it down...

 

[storlied]

You need to floor it on some gravel. lol... that's how you'll know if it's the front drive shaft... give it a good realistic test. A good one can put up with a damn good amount of abuse.

Winter is a much better time to do these kinda things.... then again... not the best time to lose your 4 wheel capability.... anyways... point is... put some stress on it and see if it holds..... also there was two different sizes by a couple inches through the years of v8 AWD's. Maybe you got the wrong one, or maybe much like me... your 'new' rebuilt part you paid for just seriously blew up within a week. or somethin.. lol... that was bs... Forget Napa, I got a Ford one and it rallies through all the abuse I throw at it.

You can also check to see if the cv joint is damaged by looking at the boot and any kinda scaring.

 

[ogwutang]

i had just put the newly rebuilt one back in and i didnt even back it out of the garage and it had popped a couple times. maybe just drive it till whatever is popping detonates?

 

[G-96XLT]

Transfer case ?

 

[ogwutang]

yeah, im going to drop it out and open it up on wednesday. maybe just replace the viscous, or might rebuild the whole thing. dunno yet. anybody know of a cheap place to get a viscous coupling?

 

[storlied]

.... Those don't pop... did you ignore everything I said? Check that joint in the shaft, like I said.. I had a newly rebuilt one and the CV grenaded itself in a week, and that's with Normal driving.

 

[ogwutang]

apparently you didnt read my post i bought a new front drive shaft, put it in, and it popped. so i took it back and they sent my core off to be rebuilt and i installed it and it still popped. the CV on the shaft is fine. when i drove it without the shaft in, there was no popping. it has to be in the TC

maybe the chain is loose and its slipping on the sprockets?