When I bought my 01' GMC EXT.Cab Z71 I was kind of surprised that I could not spin the tires in it. It seemed that the ones I test drove could do it pretty easy and they had the same options as mine with 3.73's and everything.

Did most of yours spin em pretty good when bone stock in a 4x4? Just curious if I am one of the ones with PCM issues. I have ATAP'd it and my timing tends to be in the 28-30 range at WOT. I have not checked to see how rich it is running though.

I now have 16k miles so its safe to say it's broke in also. The only way they start to spin is if I am taking a corner. <img src="gr_images/icons/wink.gif" border="0">

Once it is done boggin out then it picks up pretty good. I wonder what these things run bone stock.

 

When I bought my 2000 Z-71 5.3 3.73 there was also an identical 2001 model. I was talking to the prep guy and he said i got the better truck of the two. He said mine will turn them over for a pretty long distance(Which they do)and the 2001 wouldnt even give a little scratch. I think factory tolerances have a lot to do with it and some engines just make more power than others.

 

Does your truck have the fly by wire throttle? Mine does and it won't spin even with the whipple. The pcm doesn't instantly open the throttle like a cable would.

 

Mine's a 2wd ext cab w/ a 5.3L and 3.73 locker, it couldn't spin the tires at all, not even if I stood on the brake. Now, it'll light them up for about 100' or so, that's with me on the brake until they start to spin and then letting off. I've never tried it where I just sit there and get a big cloud of smoke going before I let off the brake, I don't want to keep buying tires.
Jim <img src="graemlins/gr_cheers.gif" border="0" alt="[cheers]" />

 

Oh yea, forgot to mention...sometimes mine will scratch when I hit second gear, with tow haul mode turned on. And I do have the locking rear diff.

[ February 07, 2002: Message edited by: Mongoose Z-71 ]

[ February 07, 2002: Message edited by: Mongoose Z-71 ]</p>

 

i have a 1999 5.3 ex.cab and mine wouldn't lay a scratch either. i put on exhaust, headers, airaide, hppIII, and i have the locking differential and i still couldn't lay a scratch. at that time i was running a 15.3. i didn't start laying huge scratches until i added on the thermostat. i thought that was kinda weird.

 

Ok, so it sounds like I am not completely alone now. <img src="gr_stretch.gif" border="0">

I am still going to check into the boggining issue. I have a standard cable driven TB just like on my T/A so I am not sure that is the problem. Coudl be something with too much fuel when you first step on it, or maybe a probem in the TPS sensor? I will start taking measurments on it all and see what I come up with.

I am not expecting this to be a tire frying beast but I am tired of the bog. It seems like it has good power at any other time though so I dont think power is the issue. I am going to change the plugs, and fuel filter on Sat so hopefully i'll get time to poke around and see whats up.

Thank you all for your replies. *crossing fingers its somethin easy* <img src="gr_images/icons/wink.gif" border="0">

 

OH helll yea!!!

I layed one nearly a block long in our industrial park when I first got the truck. <img src="gr_grin.gif" border="0">

My 8.1 has the live by wire throttle and it freely breaks them loose, so I can't see that being an issue.

 

I guess I should have specified the 5.3L motor. LOL

You damn big motor fools give me cubic inch displacement envy. <img src="gr_stretch.gif" border="0">