What tires on '96 2WD Tahoe? -Currently Unstable!

[theastronaut]

What tires would be best on a '96 2WD Tahoe? It currently has 235/75R15's on chrome 454 SS wheels. It flops around like a fish out of water and feels extremely unsafe over 40 mph. I can slowly flick the wheel back and forth and it feels like the back is swaying 4-5 inches left to right while driving, it's very unnerving at speed! It feels like it would roll over if we had to avoid something in the road. It's lowered 3.5" with spindles in front and 2" rear with adjustable shackles.

It has cheap "Star Fire" tires on it now but it's done it with other tires too. I know that it's going to have some sidewall flex with that tall of a tire but this much flex is ridiculous. I can't talk the owner (my parents) into going with 18's or 20's to shorten the sidewall.

Would adding a rear sway bar help? I currently only has a front bar.

[manimal]

shortening the sidewall will give it a rougher ride. I think the 235/75's are a 29" tall tire and kinda narrow.Maybe a "70" or "60" series would make it handle much better, and yes a rear sway bar will help with body roll. Also check your shocks and bushings.

[theastronaut]

It has had new Monroe shocks recently. We had 255/70's on it and it did the same thing, maybe not quiete as badly though. I don't think shorter tires would look right, its not low enough so the wheelwells would be to open.

I've seen rear sway bars on 4WD tahoes, did they make a 2wd rear bar from the factory?

[ksbrktracer]

I had a 2000 OBS tahoe limited and I know exactly what you are talking about. It was bad enough my wife didnt like driving it. I never did cure it either. It got better when I put 20's on it , but it was still there. Mine had a big swaybar on the front, larger than a normal tahoe (not sure of the size, but was stock on a limited). Mine only had 85K on it so it wasnt a worn out pos..... but I never did find a cure. Be interested in the answer myself.

[GCncsuHD]

So are you having side to side sway from the tires? Or are you experiencing body roll? They have two different feelings. A rear sway bar will greatly help the body roll, but won't really help the side to side sway of tires with soft sidewalls. You could consider going up to a LT tire, assuming your current 235s are P rated, it will make the ride a little rougher, but will help with the sidewalls flexing.

[theastronaut]

Originally Posted by ksbrktracer

I had a 2000 OBS tahoe limited and I know exactly what you are talking about. It was bad enough my wife didnt like driving it. I never did cure it either. It got better when I put 20's on it , but it was still there. Mine had a big swaybar on the front, larger than a normal tahoe (not sure of the size, but was stock on a limited). Mine only had 85K on it so it wasnt a worn out pos..... but I never did find a cure. Be interested in the answer myself.

Good to know that 20's helped, how did they affect the ride quality? I'm thinking that larger wheels, urethane leaf spring bushings, and a rear sway bar would make it much better.

Originally Posted by GCncsuHD

So are you having side to side sway from the tires? Or are you experiencing body roll? They have two different feelings. A rear sway bar will greatly help the body roll, but won't really help the side to side sway of tires with soft sidewalls. You could consider going up to a LT tire, assuming your current 235s are P rated, it will make the ride a little rougher, but will help with the sidewalls flexing.

It's both, but mostly the tires. I can push the back bumper back and forth a good bit with it just parked. The body lean while driving makes it feel worse I guess.

[ksbrktracer]

[QUOTE=theastronaut;5959738]Good to know that 20's helped, how did they affect the ride quality? I'm thinking that larger wheels, urethane leaf spring bushings, and a rear sway bar would make it much better.




I did 20X8.5 Boss 338 on 275/45/20, they really werent tall enough , but my wife wouldnt let me lower it, It didnt seem to affect ride much at all, but it definitely helped the tire sway issue. You could rock mine sitting still also. I had new shocks, poly sway bar bushgs etc....couldnt make it go away 100%. Ive had other tahoes that didnt have that problem.

[sntrym95]

You may want to consider new leaf springs. After replacing mine in my truck it was night and day difference.

[1badgmc]

There is A LOT of weight in steel and glass over the rear wheels. You should feel the sway in the longer wheelbase of a Suburban. A lot of what you're feeling is just the nature of a big SUV. A rear swaybar will help to flatten it out in turns, but most of that sway is from the tall sidewalls. Shorter sidewalls would do a lot to calm that issue down. Some 17s or 18s and some tires with enough sidewall to keep the overall height near stock would make it a lot better without sacrificing much ride quality, but if your parents don't want to go with larger wheels, then there's really not much you can do about it other than shorter tires, but you're right, with such a mild drop, that can look a little off.

[GCncsuHD]

Originally Posted by 1badgmc

There is A LOT of weight in steel and glass over the rear wheels. You should feel the sway in the longer wheelbase of a Suburban. A lot of what you're feeling is just the nature of a big SUV. A rear swaybar will help to flatten it out in turns, but most of that sway is from the tall sidewalls. Shorter sidewalls would do a lot to calm that issue down. Some 17s or 18s and some tires with enough sidewall to keep the overall height near stock would make it a lot better without sacrificing much ride quality, but if your parents don't want to go with larger wheels, then there's really not much you can do about it other than shorter tires, but you're right, with such a mild drop, that can look a little off.

Agreed, back in ~2000 we got my mother a set of Enkei 18x9s with 285/60R18s, this was back when 20s were pretty much unheard of except in magazine. It drove nice and stable, and my mother never complained about the ride. It was stock height, not lowered though. I would say some 17s with say 235/65R17 with an XL rating would suffice? You would keep the same overall dimensions as you currently have, with a shorter/stiffer sidewall, but not so thin that it makes the ride rough.

Her old Suburban:

Same wheels, years later on our C1500 work truck, just a better picture that above.