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99 Z71 Rattling underbody


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Posted

My stinking truck has been a headache since day 1--hums when I turn left--only left? ABS motor fried about 3 months ago--I am happy about that. when you shut the door the rear window pops open. Gas gauge dances around--if I jerk the truck it shows how much gas there is for real. Now the latest--it sounds like I have about 50 plastic shopping bags dragging under the truck--but only when I am going fast than 5 miles per hour. Obviously I can's get under there and see what the deal is while I am moving, so I was wondering if anyone else has had this problem and what I should be looking for. I know this is a real hard question cause it could be any of a million things, but I am really hoping someone else can give me a clue as to whether it could be my transmission and if it is going to fall out on the ground--The leaf springs are very squeeky--but I am pretty sure that they are not making this noise--more like a rubbing/flapping noise. I would appreciate any help you can offer--if only so the shop doesn't charge me an arm and a leg when I take it in. Thanks

Posted

Hums-- that has happened occasionally on mine. I think it is a surprised power steering pumps -- but it only happens spiratically... the gas guage problem is a faulty sensor in the fuel tank-- What year model is your truck?

 

for the plastic bag sounding noise-- check the plastic that lines the fenderwells under the hood & under the truck. if these parts are making the noise, then they will be worn down where they have been dragging or rubbing. It may only due it at 5 mph because after that speed, the wind resistance is enough to lift the piece away from whatever it's dragging against. it is possible that there is a piece hanging on the driveshaft.

 

Check those things, and try driving about 5mph with just the driver window down, then just the passenger window to isolate the noise more.

 

hope this helps

Mark

Posted

I think the noise is coming from the transmission. I checked fluid levels and then crawled under the truck and see the transmission is covered with oil. The bar coming out of the casing is actually clean for about 1/4 inch--chrome and looks brand new--like it pulled out some 'cause the rest is rusty and dirty. Oh and there was a plastic bag under there too--a newspaper got thrown between the bed and the cab--DUH. Tell me this might not cost me thousands of $'s. The truck has been rear ended twice--I mean these little rinky dink cars have driven under me and lifted the bed off the ground. Started making funny noises after the first time and has not been fixed since the second time--but it has been months since I was hit last--could being driven under caused this type of problem?

Posted

Oh and one more thing--the ABS motor went out a couple of months ago--I don't like ABS--it slips and gets mushy at all the wrong times. So at this point I pulled the fuse and just don't worry about it. I know I can have it fixed for 115 by this guy on the net, but I would just as soon leave it the way it is--is this a problem or does it matter at all? Thanks

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