Problem pop clunking noise 1999 Seirra

[raynerex01]

Thinking about buying this truck but there's an issue truck starts sounds good in neutral pit into gear still so far good start driving there's a popping and clunking noise you can feel under the floor and the truck seems like it's being held back sort of until you get the rpms over 1500 then the noise goes away and it seems fine until you shift Into the next gear the rpms go back downa an it does the same thing till revved back up transmission seems fine truck is 5 speed with 4 wheel drive if anyone can tell me what this is it'd be greatly appreciated

[02suburbanZ71]

Sounds like a bad slip yoke possibly? I get a little jolt under slow acceleration or while turning because the splines get rusty and then it binds up. It makes a clunk going into gear. Or a worn transfer case.

[raynerex01]

Well I don't notice going into gear because it's a standered is there anyway I could seperate the two anything major I might notice that I should know if it's the TC or the slip yoke

[raynerex01]

Also the truck has been sitting 2 months if that means anyrhing

[02suburbanZ71]

Put the rear end on jack stands, chock the wheels, have someone give it gas, listen/look under vehicle for cause. That will help pin point

[woodm]

Better have a really close look at the frame of the truck, especially where the body mounts are located. This sounds to me like you might have a broken frame rail or crossmember somewhere...yikes!!

[raynerex01]

Is it possible it's just a really bad u joint lol I'm checking it out Tommorow just wondering what to look for I did look all cross members good and no cracks or anything

In the frame

[raynerex01]

Or I was thinking a bad slip yoke even I just don't want it to be somthing to exspensive under 400 dollar fix hopefully also I have a miss fire but only when revved up any ideas on that?

[brucelimerick]

Almost for sure a u-joint. Cheap fix, do both. I drove from Detroit to Calgary with a bad one. You keep tension on it and it will stay quiet. Take the pressure off and it thumps like mad. Light brake will help with shifting. You have 4 wheel and I had 2. I'm not sure of the configuration of the front end but it sure sounds like the rear drive shaft to me. They are cheap, less then $20 each. Watch the rear grease nipple, my 2001 you have to drop the shaft on the ground to grease it. You can't get the grease gun on to it when the shaft is installed.

[02suburbanZ71]

If it is the slip yoke gm has an updated version made from nickel. Service bulletin #01-04-17-004B:

 

Hopefully i can get one, .... One day

[raynerex01]

Alright well I'll take a look for everything you've all mentioned taking it into shop today so I can get it on a lift cross fingers hope it's not somthing big thanks for all your help

[raynerex01]

Got truck up and found the issue barbed wire wraped up stuck in the front universal all that's left is a misfire and I've decided to purchase the truck