Are new wheels supposed to feel like stock?

[Chowder]

I have a 2012 SR5. I recently got a new set of Ultra Bolt 17x8 wheels with a 10mm offset. I am running 285/70/17 tires with the wheels. I got the tires before I got the wheels and they felt great with the stock wheels. They rode smoother than stock and tracked straighter down the road. I assumed that they would feel the same and look better with wider wheels so I bought the Ultras.

However, there is more road feel (bumpier) which isn't too bad but what really bothers me is how much bump steer there is which was nonexistent with the stock wheels. When making a turn at an intersection, the steering wheel jerks hard left or right when it hits a bump. The wandering is back and is same as stock. The only good thing is that the Ultras are lighter and there is less steering wheel effort when turning. I know a lot of members are running 10mm offset wheels. Is this bump steer normal or did I get the wrong offset? TireRack lists 10mm offset but they also list 0 offset for another brand.

 

[Antman]

I have a 2012 SR5. I recently got a new set of Ultra Bolt 17x8 wheels with a 10mm offset. I am running 285/70/17 tires with the wheels. I got the tires before I got the wheels and they felt great with the stock wheels. They rode smoother than stock and tracked straighter down the road. I assumed that they would feel the same and look better with wider wheels so I bought the Ultras.

However, there is more road feel (bumpier) which isn't too bad but what really bothers me is how much bump steer there is which was nonexistent with the stock wheels. When making a turn at an intersection, the steering wheel jerks hard left or right when it hits a bump. The wandering is back and is same as stock. The only good thing is that the Ultras are lighter and there is less steering wheel effort when turning. I know a lot of members are running 10mm offset wheels. Is this bump steer normal or did I get the wrong offset? TireRack lists 10mm offset but they also list 0 offset for another brand.

Same air pressure in tires?

 

[Chowder]

Yes, same air pressure. Both were set at 36psi.

 

[Antman]

I'm not an expert here- but I would be willing to bet the difference your feeling is related more to the difference in wheel widths, not the offset. Stock SR5 wheels are 7". The tire contact patch will be "rounder" on the 7" wheel and "flatter" on the 8" wheel. Big flat contact patches tend to tramline more- follow grooves in the pavement and such- like you are describing. I would experiment with tire pressure a bit if I were you.

Maybe I'm wrong, but that's my .02!

Good luck :zoom:

 

[4RBob]

did you get an alignment when you got the wheels? if so, any numbers look a lot different than your last alignment?

also, how does the tire balance seem? any shimmy at certain speeds? although, a lot of your symptoms don't sound like a tire balance issue.

 

[Qjake]

Interesting, not that it should matter much but what tire are you running I'm surprised that there is that much of a noticeable difference. As Jeff said experiment with tire psi and I guess having your alignment checked wouldn't hurt. Good luck!

 

[Chowder]

I will play around with the psi to see if that helps. I bought the wheels at Discount Tire and the manager said that I didn't need an alignment just for new wheels. I will take it back to Discount and have them check the alignment.

Hope I didn't get the wrong offset. I can't find the backspacing anywhere on Ultra's website. I will email them.

 

[Qjake]

Wheel offset/backspace chart. Credit [MENTION=8206]harper7[/MENTION]



Agreed you shouldn't need an alignment, swapping wheels and/or tires shouldn't affect it at all, but neither should the offset/backspace.

 

[FERAL 4R]

I agree with Antman.

I would still get an alignment though and get as much + caster as you can.

 

[Chowder]

Well I got an email back from Ultra that says that the backspacing is 4.88 inches. According to the backspace chart, 10mm offset looks reasonable.

I suppose I just have to get used to the bumpsteer. I guess those that are running 9" wide wheels must be getting the same or more bumpsteer. BTW, I am running Toyo Open Country AT2s.

Thanks everyone.

 

[Qjake]

I guess those that are running 9" wide wheels must be getting the same or more bumpsteer.

Thanks everyone.

Nope not at all :nono:

 

[Canazes9]

Well I got an email back from Ultra that says that the backspacing is 4.88 inches. According to the backspace chart, 10mm offset looks reasonable.

I suppose I just have to get used to the bumpsteer. I guess those that are running 9" wide wheels must be getting the same or more bumpsteer. BTW, I am running Toyo Open Country AT2s.

Thanks everyone.

I also agree with Antman - it's probably due to the extra width. I would do as Antman suggested and experiment with air pressure. Try bumping it up to 40psi and see how it feels.

David

 

[swimmerdude1127]

Well I got an email back from Ultra that says that the backspacing is 4.88 inches. According to the backspace chart, 10mm offset looks reasonable.

I suppose I just have to get used to the bumpsteer. I guess those that are running 9" wide wheels must be getting the same or more bumpsteer. BTW, I am running Toyo Open Country AT2s.

Thanks everyone.

Did you ever get any resolution to your problem here?

 

[Scott@Hightech]

Although this is an older thread, id like to throw my 2 cents in.
1: The wider wheel will change the contact path like Antman said. that will change a lot of "road feel".
2: Often time pushing the wheel out further can change ride height slightly(More leverage on the suspension). It may not be noticeable to the eye or even a tape measure. It may change it just enough to decrease toe to where it changes handling. remember your dealing with Hundredths of a degree.
3: The wheels being lighter will make the ride significantly rougher in most cases. Rotating mass is good and soaking things up. Most people change wheels and tires at the same time so they dont notice it as much or just assume its normal.
4: Make sure the tire pressure is correct for the current load range tire. If you had load range C tires that wanted 32 psi and now have LR E tires that should have 65 in them, they will ride like complete crap at 32.

hope that helps if you havent figured it out yet