Just back from the shop with a question for you guys. First a brief history:

About a year or so I got a hold of these 305/70-16 Wrangler AT/S from a friend. One pair had ~90% tread, while the other pair had ~50% tread at the time due to him replacing a pair after he got a nail in one of the originals. Zero problems with the size desparity between them; maybe 1" in diameter, for the whole time I've owned them.

Fast forward to today, I replaced my rear set that had maybe 10% treadlife left while the fronts have about 40%-50% left on them. As soon as I begin my treck home, I immediately feel a difference in the truck. She's a whole lot looser in the steering, especially at highway speed (60 mph) and she pulls a bit to the right. The most disturbing thing that happens is that my ABS kicks in during moderate braking (Completely dry out). Before I had to stand on the brakes to get the ABS to activate. They balanced out real well, no shimmy or shakes at all.

I stopped and check the tire pressure and it was all good. So, is the increased diameter, 1.5 inches at the most I'd guestimate, really unbalancing the truck this much, or could it be something more serious?

 

I wouldn't think that the increased diameter could make that much of a difference...is it possible that one of the new tires has a defect? Were they roadforce balanced? Possibly a shifted belt or flat spot? On a large tire like that, spin balancing isn't always enough. As far as the abs goes, maybe some rust got knocked on to one of the sensors upon the removal/installation of the tires. Wouldn't be a bad idea to put it back in the air and check the wheel bearings also...a bad wheel bearing will make the steering feel loose, possibly cause a vibration, and do wacky things to the abs. If you had to hammer any of the wheels off because they were rusted to the hub, one of the wheel bearings might have gotten wiped out.

 

Defective tire(s) maybe, everything feels great as far as ride quality.

They were spun balanced afaik, this shopped did a great job balancing them when I first got them, hence the repeat visit.

It's pretty clean under the tires. Just had them off to touch up the paint on my calipers the other week, so I don't think any dirt or debris would be suspect.

This happened at a rather crappy time since I am supposed to swing up to DC tomorrow, but may need to cancel the trip, rotate the tires, and maybe take it in for an alignment.

Thanks for the suggestions!

 

my toyos bounce at 40 to 50 but ive learned to ignore it

 

Well after breaking 2 ratchets and 2 adapters trying break a lugnut loose to rotate the tires, I may have found the problem. Seems like the kid who put the tires on torqued the damn lugnuts at tight as possible. This is my pet peve with damn shops. How the hell is anyone supposed change a tire after someone hammers away with their air impact.

Now I have to try to find the time to get up there and talk to the guy I know who owns the place before he moves.

I'll replace the broken tools when I'm at Sears later on this week. Now lets just hope my rotors aren't warped. Anything else I should look for?