jsmith823

Hey everyone, I have a question about backspacing. I have searched the forum and couldn't find exactly what I'm looking for. Basicly, I have 31x10.50 15 inch duratracs mounted on stock cherokee sport wheels. I am planning on upgrading to a 15x8 rim and I'm wondering what backspacing I will need. I am looking at the Dick Cepek DC2 wheels (http://www.ntwonline.com/15X8-5X4.5-...l#.UqDZSsRDvto), which have a 3.625" backspacing. My question is, how far will these stick out? I don't like the "roller skate" look, and would prefer to keep them as close to being under the stock flares as possible. The other question is how little backspacing is necessary to keep from rubbing on the LCA's ? At a little less than full lock I rub pretty good. Thanks!

DieselDaze

the higher the number BS the closer in the tires are?? I was looking at these wheels http://www.ebay.com/itm/400252231407...84.m1423.l2648 and asked about them in the sticky thread..

someone said he had 3.75BS and with the wheels I showed him it would be hardly a noticeable difference with 1/2" sticking out...

I'm in the same boat as you and have stock flares and don't want any major issues so I'm curious about the answers you get here..

Atmos

5" is stock back space
4" on 15x8 is the most common aftermarket replacement among the jeepers
3.5" will stick out .25" farther on each side than the 4" will

in other words there is some difference, but bewteen 4" and 3.625" you will hardly notice
and keep in mind that the more offset you get, the more stress your balljoints and hubs will see. however minimal

those dick cepeks will work fine. order away

PocketsEmpty

4" backspace and those stock flares should be perfect.

DieselDaze

good to know....

question... do you think the link I posted with a 3.5" lift and 31's will work without rubbing??

XJmike0122

I have had 3.75 inch backspacing wheels with 31s on the TJ for 7 years. I'm not saying your wrong just giving some sort of time frame.

Atmos

damn. you guys are both ordering up some fancy rims
yeah they will definitely work

I should have put more emphaisis on the "however minimal" part. not a huge difference from 4", but it does put more stress the farther it sticks out (however minimal that may be). I burned through 2 unit bearings when I was running my 35's and 3.75" backspace

XJmike0122

No I got the minimal part. Like I said I was not disagreeing with you. The bigger tires might have something to do with it. How long did it take to go threw 2 bearings?

Atmos

6 months but that's with heavy abuse and I replaced them with other hubs I had laying around. not brand new. they were in good shape though

XJmike0122

Hah. The TJ never really sees that much abuse. Probably another huge factor.

jsmith823

Thanks for the replies guys! I'm just gonna go with the dc2s then.

salad

Stock rims are 7" wide with 5.75" BS. Stock tires are about 8.9" wide (225/75R15). This puts the inner edge of the tire (well, section width) roughly 7" over the WMS of the hub. With 31x10.5R15s on stock rims you get 7.5" hanging off the back.

When you move from a 7" rim to an 8" rim you immediately gain 0.5" with the same backspacing. That is to say your tire sticks out half an inch further, but also you gain half an inch of clearance from suspension and steering. Of course the tires are larger in diameter so rub places the stock wouldn't have rubbed before.

On 15x8 rims and 4" BS (pretty common) you only end up with 5.25" hanging over the hub's mounting surface. You also wind up with 5.25" over the front of it, whereas the stock setup gets you 1.9". So your new setup will have the tires approx 3.35" out further than stock.

Note all of this is referring to section width, which is not the same as the total width of the tire since sidewall often sticks out further. But that doesn't matter very much in terms of fender flares keeping down the spray of water or mud, or in terms of rubbing suspension or steering.

On my 1999 with 3.5" lift (up front anyway lol) I installed fixed RE LCAs. I only have rubbing at full lock, I'm on 31x10.5R15s with stock Ecco rims. An 8" rim would probably fix my issues, since this is my daily driver and I plan on staying with 31s forever I'd really be fine with an 8" wide rim with 5" backspacing, and not need to worry about "the roller skate look" or getting a ticket for tires out past fender flares.