Random Wheel Related Questions

thelostartof · March 13, 2008

Ok so I know this is newbish and my first post here, so please be gentle with me.

I am helping a friend fix up and get their truck back up to spec. Truck is an '03 GMC Sierra 1500, 2wd, 5.3L V8

Right now I have a few pretty basic questions. I have been searching for the last few days and found out loads of info which have helped me almost figure out for sure what is wrong with the ABS system(still testing stuff before i pull the module and send it off).

Either way on to the questions...

I just threw on some 265/70/16 (Yokohama Geolandar A/T-S) tires on stock wheels that we picked up local for cheap with about 10k on them, what kind of tire pressures should I run these at? I have read numbers around 50-60 psi but coming from a world of cars it just seems like a lot of air pressure, never mind the max rating numbers on the tires. SO I just wanted to what kind of pressure would you run? Truck is daily driven and sees very little time off road, along with is never really loaded up so the bed is almost always empty.

Also what is the torque spec for the lug nuts?

Next is where is a good place to find some stock lug nuts? right now the truck has some larger acorn nuts on it that keep us from running the stock center caps. I am pretty sure the lug is a M14-1.5 in size and all local parts stores show those lugs being around $2 each which is semi insane in my book as for car parts I can get new basic lugs for my car for around 20 cents each so I was wondering if there are any say online sellers that offer them cheap? or should I just put up a wanted add for a set of stockers?

Last would be is there any trick to removing the brake caliper bolts? I just changed the front hub on this truck(this is the 2nd time they have had that one replaced in the last 2 years) and I went about it the easy way just removing the entire caliper bracket as with the T55 bit the caliper bolts would not come loose.

Otherwise I think for now that is all I need to know. I am sure there will be more as I start to fix up all of the little stuff on this truck. So far Search has turned up loads of info and I still have a few more weeks worth of reading and searching. Right now I am dealing with the joy of the ABS and brake light being on all of the time sans for the few random times it turns off and then back on. If I go more than say 50% on the brakes it feels like the rears lock up as the rear end kicks out and leaves two black marks. I am going to spend this weekend chasing things down to try to make sense of what is wrong with the system. Right now it stops just fine as long as you do not nail the brakes.

Thanks

Mike

bossier62guy · March 13, 2008

I've run 35psi in every tire I've ever driven my truck on and the lug nut torque should be 140 foot pounds. Can't help you w/ the other questions but good luck!

marko · March 13, 2008

Ok so I know this is newbish and my first post here, so please be gentle with me.

ANSWER: No problem. The only bad question is one that is unasked.

I am helping a friend fix up and get their truck back up to spec. Truck is an '03 GMC Sierra 1500, 2wd, 5.3L V8

Right now I have a few pretty basic questions. I have been searching for the last few days and found out loads of info which have helped me almost figure out for sure what is wrong with the ABS system(still testing stuff before i pull the module and send it off).

ANSWER: Not too good to mess with ABS on a "friends" basis. Learn what you think is wrong, diagnose the problem, but then have an accredited GM service center fix it. A malfunctioning ABS system can cause an accident and you don't want to be responsible for that, even if not legally, you will still have to look in the mirror every night. Leave a safety-related job to a licensed, accredited service center. (Hubbycap, how do you like my American spelling?)

Either way on to the questions...

I just threw on some 265/70/16 (Yokohama Geolandar A/T-S) tires on stock wheels that we picked up local for cheap with about 10k on them, what kind of tire pressures should I run these at? I have read numbers around 50-60 psi but coming from a world of cars it just seems like a lot of air pressure, never mind the max rating numbers on the tires. SO I just wanted to what kind of pressure would you run? Truck is daily driven and sees very little time off road, along with is never really loaded up so the bed is almost always empty.

ANSWER: You can run these at 40 psi. I run my truck at 40 psi because it's a 1500 and generally not loaded. 50 or 60 psi is max pressure and will make it feel like you are riding on cement wheels.

Also what is the torque spec for the lug nuts?

ANSWER: Torque specs are 120 pound-feet. Retorque after 100 miles!

Next is where is a good place to find some stock lug nuts? right now the truck has some larger acorn nuts on it that keep us from running the stock center caps. I am pretty sure the lug is a M14-1.5 in size and all local parts stores show those lugs being around $2 each which is semi insane in my book as for car parts I can get new basic lugs for my car for around 20 cents each so I was wondering if there are any say online sellers that offer them cheap? or should I just put up a wanted add for a set of stockers?

ANSWER: Not really. These are the 7/8 nuts. You can get them from a jobber or from GM but they are not cheap. Sorry.

Last would be is there any trick to removing the brake caliper bolts? I just changed the front hub on this truck(this is the 2nd time they have had that one replaced in the last 2 years) and I went about it the easy way just removing the entire caliper bracket as with the T55 bit the caliper bolts would not come loose.

ANSWER: Not really. The trick is to use never-seize when you install them, but only on the machined shoulder. What happens is that the shoulder (that goes thru the caliper) rusts to the caliper and they are hard to remove. The threaded part probably never does seize. The calipers have therefore probably stopped floating on the shoulder of the bolt. You will have to use heat which will probably fry the caliper seals, and may boil the brake fluid, or even wreck the hubs. I would suggest hitting them with a hammer (ball pein) and giving them some penetrating oil and letting them sit for a day or two. They will break loose after that but it will take patience!

Otherwise I think for now that is all I need to know. I am sure there will be more as I start to fix up all of the little stuff on this truck. So far Search has turned up loads of info and I still have a few more weeks worth of reading and searching. Right now I am dealing with the joy of the ABS and brake light being on all of the time sans for the few random times it turns off and then back on. If I go more than say 50% on the brakes it feels like the rears lock up as the rear end kicks out and leaves two black marks. I am going to spend this weekend chasing things down to try to make sense of what is wrong with the system. Right now it stops just fine as long as you do not nail the brakes.

ANSWER: Again Mike, don't mess with safety systems. Diagnose that problem and then get somebody licensed to go over your work. Regular brakes are easy enuf to do, but when you are messing with ABS you can do more harm than good. You can go to the extent of fixing the problem as you think it should be fixed, but then book an appointment with your GM dealer to make sure you have it right. Don't take chances on this one.

Thanks

Mike

Hope this helps.

thelostartof · March 13, 2008

Thanks

The ABS issue I am not super worried about as I have build stand alone computers for engines before, I just need to understand the concept of how things work to make sense of it. From the few dealer techs I know I think I have figured out the issue w/ the ABS system and it looks like it is the same Module issue that everyone else has been having with these trucks so I am looking to remove it and ship it off to have it upgraded. a non functioning ABS system is no where near as bad as a system that will randomly lock up the rear and cause the truck to slide out of control. Plus if I left it to a pro to fix the ABS they would never be able to afford to fix it.

I am just adjusting to newer cars where you have to use computers to scan for codes as the euro cars I have been working with for the last few years all have build in diag systems that let you read all ODB and ABS codes w/o any special tools.

Either way I am not going to touch anything until I diagnose everything for it