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DeepVee
10-15-2002, 12:42
I was towing a 6,000 lb. load this weekend and noticed a rattle or chatter noise coming up through the shifter handle. The noise would only appear when I loaded up the drivetrain, i.e. going up a hill or accelerating. This is at highway speeds in 6th and 5th gears.

Has anyone else noticed this? I'm wondering if it's related to the noise Ford ZF owners complain about. GM claims they fixed the problem by adding a bushing at the base of the shifer.

jjgmc
10-15-2002, 19:46
Have 2002 gmc reg cab dmax six speed Have towed gooseneck tralier 24,567 gcw have not noticed any noise at all got 12mpg towing 20.5 mpg empty very happy all at 12,543 miles just gets better and better

crafty
10-15-2002, 19:54
I've got 39,000 kms on mine ad I towed 15,900 lbs GCW on an 800 km trip on the 401 and had no rattle at all. I got 16.4 mpg (imp gal.) while towing.
:D :D :D

spctr13
10-16-2002, 00:20
I have 57,000+ miles , 75% towing 26' travel trailer to all four corners of the US . Transmission and dual-mass flywheel replaced @ 35,900 miles , 2nd dual-mass flywheel @ 52,000 miles . Noise during downshift mostly 3rd to 2nd , but quite apparent at idle ,transmission in neutral , at last inch to inch and a half of clutch travel . A total of four flywheels were sent to get 2 that were usable . Each time the first was sent in a " plain brown wrapper" and came through with a mounting dowel broken . In all the truck sat at the dealers for better than 3 weeks . I don't know if this is your problem , but a quick check is to work the clutch , transmission in neutral , engine running , last 1 - 1 1/2 inch of travel ( top ) .

Mac

DieselDennis
10-16-2002, 09:01
Did you try to stop the noise? It could just be a loose shift knob. Did the rattle occur in any gear? Maybe just overdrive? Still running stock fluid ( non-synthetic? ).

Does anyone think the engine has anything to do with this? I don't really think so. But we have two people complaining about it. One drives a gasser and one (spctr13) that doesn't say he has a diesel. While two that the diesel don't have any trouble. Just a coincidence I'm sure.

Colorado Kid
10-16-2002, 13:05
The stock fluid in GM ZF 6 speeds IS synthetic. GM chose to use synthetic fluid in lieu of the oil pump and cooler that F*rd uses.

Mine is quiet and smooth, but my buddy (who also has a D-max ZF) just mentioned to me yesterday that he has a rattle under load in 5th and 6th gears when towing his Scout on a flatbed. He first noticed it in 6th when towing, but says that he can now provoke it unloaded in either gear. He hasn't run it by the dealer yet, but will well before reaching 36,000 miles. (about 13,500 for mine and 15,500 for his right now.)

DeepVee
10-16-2002, 15:21
The shifter handle is tight and is not generating the noise. I had a loose handle on my 96 and would recognize the noise.

I pushed on the handle and the noise did not change, which makes me think it's being transferred up from the transmission gearing or possibly throw-out bearing.

The noise is not super loud and can't be heard if the radio is on. On this trip I just happened to be driving with the radio off and discovered the noise. I need to go out on the freeway again with no load and see if I can make it happen. If so then I'll take it into the dealer. Although I can guess they're response, "Can not duplicate at this time".

Thanks for the response guys. Colorado Kid, your buddy’s noise sounds the same as mine. I'm currently at 17,000 miles. I have no noise at idle and the clutch/flywheel seems to be fine, although my pedal assembly was just changed, due to pop happy spring.

[ 10-16-2002: Message edited by: DeepVee ]</p>

Colorado Kid
10-17-2002, 11:14
I'll give you the same advise I gave my buddy...when you take it in insist on taking them for a ride and demonstrate the noise for them. Otherwise you will get "Unable to duplicate customer complaint."