I'm a new member with '08 H-3 Base Model and been looking to replace stock 16" wheels with KMC XD Monster 20X9's with 305-50-20 tires. Have a Truxx front end leveling kit on the way. Should lift front about 2-3 inches according to them.

Getting some conflicting info from the different wheel dealers on proper wheel offset though.

Overal diameter of this tire on 9" wheel should be between 32" -33". Was told 32.9 by one place.

The offsets being recommended by different wheel dealers are either +18mm or +35mm.

The Truxx lift kit dealer says problem with H3 is rubbing on back of front fender when tight turning, so says to be careful about an offset that throws wide wheels too far out there. The higher the + number the further in the wheel, is my understanding. The OEM wheel offset suposed to be like +38mm ? Supposedly the lower + numbers or any neg numbers will throw the wheel more outward.

Wonder if anyone running 305-50-20's on a 20X9 wheel on an H3 and what might the offset be?

 

I'm running 305/55R20s on my 20x9 rims with a +18 offset. I struggled with the same decision you are facing and would recommend +18 at least. There are no rubbing issues with my setup at all but I was concerned with the tires sticking out too far past the fenders, which is illegal in many places. Mine do stick out over an inch beyond the fenders in the rear but I am hoping to get away with it. If you can find rims you like in the +18 to +30 range I would suggest you will be fine. Here is a link to a tool you should find extremely handy in this regard: Custom rims, wheel tire packages for your ride - RIMSnTIRES.com Just put in the stock info on the left and your potential new rim/tire info on the right and then scroll down to see a description of what you can expect.

PS I have leveled my H3 by just turning the torsion bars up in the front which is ridiculously simple to do and free to boot so I strongly urge you to cancel your leveling kit order and do so as well. Search around on this forum and you will find many people who have done the same and recommend avoiding wasting your money with a kit which doesn't allow you to do anything that the stock equipment doesn't.

 

Tire diameter has nothing to do with wheel width. It has everything to do with TIRE width (305) and aspect ratio (50/55) and wheel DIAMETER.

305/50/20 will be 32.0" diameter
305/55/20 will be 33.2" diameter


32" diameter is too small in my opinion. It just doesn't fill the wheel well properly, especially on a leveled truck. Get a 33" diameter or larger.


And CANCEL the leveling key kit. IT IS A WASTE OF MONEY.
A torsion bar adjustment does the same thing for FREE.
Look in the FAQ section for instructions. Takes all of 20 minutes to do.

 

Thanks, I appreciate all the info. Might be too late to cancel the leveling kit since it shipped out...but might be able to return it.