I know there is many topics on backspacing and tire sizes throughout this, but I cannot find a straight answer to what I need. I currently have a set of 33x12.5 BFG AT KOs with some aluminum wheels I don't know the backspacing on, but they stick out quite a bit. I have a 3" lift and Shrock bumper. They rub very badly when I turn more than 1 whole turn, and if I hit a bump, forget it. I wanted to get some black steel wheels that would rub the least and wouldn't be sucky when I wheeled. I was thinking about going with a 4.75" backspacing but I really have no clue what would be the best answer. If someone could please help me with the best backspacing for the tires I would be super happy, I am tired of the rubbin'!

Thanks!

I have 33/12.5's on 4.75BS, you want 5.5 stock BS, trust me, the 4.75's stick out too much

I'm looking to switch mine from 4.75 to 5.5, just saving some green

Check this site out: http://www.rocky-road.com/wheels.html

Thanks for the quick reply, a few concerns...

But wouldn't you want to go a bit less of a BS so that the tires don't rub inside the wheel wells against the truck due to the wider tire than stock? If you kept the stock 5.5" BS with the much wider tires, wouldn't when you turned the tires would hit the frame up front and when wheelin' and you stuff the rear wheels wouldn't they rub the frame inside? So maybe a 5" BS would suffice? Again, I haven't a clue, that is why I am asking, I am just throwing thoughts out as they come to me...

Yes, they will definitely rub like a mofo in the rear.

The stock BS is ~5.075, on a 7 inch wide rim. On a 15x8, a 5.5 BS will give you pretty close to factory offset. With stock wheels, I rub in the rear when articulating (with 32s). I do not know what the consequences will be in the front with 33x12.5s, but mine doesn't seem to be close to rubbing.

Good luck.

My rears are at least 3.5"~4" away from the frame with 4.75

JeffW-

So do you think a 5" BS would be a better decision for me then? I was thinking that the 5.5" would be way to close to the frame. I am just tired of rubbing...and I want black rims. Most importantly I want the best BS for the least amount of rubbin'. I could have gotten 32" tires, but I got a great deal on the 33s I got on there...

Perhaps sitting there, but at full flex, even a 4.75 BS should be rubbing with a 33x12.5s.

I have 32 x 10.5 and they are rubbing with the stock 40mm offset. So a 33 x 12.5 will absolutely rub at even an additional inch of offset.

What width rim do you have? That (with backspacing) determines offset. Backspacing is not really meaningful by itself.



You may not be able to eliminate the problem without a body lift or more extreme suspension lift (such as SAS). Trimming wheelwells and adjusting bumpstops may help, too. Personally, I would rather have a wider stance and go for the BL with some trimming.

TJ, or somebody pipe in here!

I have the BL with trimming it rubs using 4.75BS in the front on the metal near the door under compression wile turning due to being to far out of the wheel well

JeffW-

I need to figure out what my BS and offset is, I forget now. I will ask the guy I bought them from. I would rather not get a body lift due to the Shrock bumper and sliders.

TunaSoda-

So with your setup [4.75" BS], can you compress your back wheels completely without any issues? Also, do they rub up front when you are turning or slightly turning hitting a bump [say going up the driveway]? Maybe 4.75" is the best I will get? I wish someone with 5" backspacing with 33x12.5s could chime in...that would be super!

Thanks for the help aready though guys, the internet is so awesome.

I'm not sure about the back, I do have a 2"BL and the front will rub when steering around or more than say 45° or so (only under compression)

TunaSoda-

I think the back wouldn't really make a difference with a BL because I was worried about it hitting the inside part of the fenderwell, the part against the frame area, so a BL would only move it up, not out of the way, did that make sense? Now the BL up front sure helps I am sure, I guess I just need to figure out what my BS is currently. I am fairly certain it is either 4" or 4.5", because when I hit a puddle or anything, it is all over the side of my car for sure...that gets rather annoying too...I think 5" might be the way to go but I need to figure out what mine are right now. If I am assuming correctly, the less the tires stick out, the more you will be able to turn the wheel without rubbin'?

Yes, the higher the number, the more pulled in the wheel is into the well.
Do you have a pic of your setup?

Here is how mine stick out with the 4.75:

Yeah, let me go home and post one...probably in like an hour. Mine look much like yours but I sorta cannot tell since we have quite different tires...

Less backspacing makes it more likely to rub on the fender, more backspacing brings it closer to the frame.

To compute offset from backspacing:

Ofst(inches) = BS - (width/2)

Ofst(metric) = Ofst(inches) x 25.4 = [BS - (width/2)] x 25.4

Backspacing from metric offset:

BS = (Ofst/25.4) + (width/2)

Good luck!

Here is a picture of it when it was clean...

Nice X!

Are you getting any rub at all on the rear tires?

I would guess that you have a BS similar to mine of 3.75. Mine do not rub anymore. I have a 2"BL and PML. However, I am still running 31x1050 tires. When I make the jump to 33x1250, I will get crager soft 8's with 4.75 BS.

You could always buy some desert runner rims on ebay for about $500.

I noticed you have no Body Lift. That is a cheaper way to stay with the same wheel/tire combo you currently have. You will definatley not rub with the body raised 2"...especially if you adjust your steering stops also.

I prefer the look and performance of a wider stance, myself. I like the way you truck looks-similar to mine. Might consider the 2"BL.

Hope this helps.

ETA: With that wide stance and big meats, you should really consider getting a HD steering setup. Just FYI...

That is what I have, it sucks as far as front rubbing (plastic is gone, metal is trimmed in about 1.5")

Nothing my handy dandy litlle sawzall can't cure!



ETA: you probably would not have any issues with a full 3" lift added to your 2"BL and PML. You truck look great by the way.

Not true, we used an air powered cutter and it can't be trimmed back anymore without cutting through the floorboards

You mean adding the extra inch?

An extra 1.5". since that is what you had to trim back from you front fender, right?

I might have to go that route, not that I want to spend that kind of money for the inch or so, and I will have gaps bumper-wise

How will your bumper have gaps from a suspension lift? Don't you have a 2"BL and 1.5" PML??? Bumper gaps only occur from body lifts.

I thought you were refering to going from a 2" BL, to a 3" BL
I was mistaken
A full 3" SL will still stuff to the same point won't it?

sigh.

OK - For 33's -

OK - the summary of the BS is correct, less BS sticks out, more BS tucks in tighter.

When the tires stick out past the fenders, and you stuff straight up...the tire will hit the fender, unless to cut off that part of the fender, raise it, etc.

REAR - When you stuff one side with the OTHER side drooped, the arc the stuffed tire swings through on the way up, brings the inside top edge of the stuffing tire right at the frame...

...this means that the small BS that makes you rub on straight compression, helps you CLEAR the frame on "opposite side drooped" compression.



Yeah - I know...its a mess back there...

So - for the rear...you can get away with less BS, as most stuffage is one side at a time...unless you do jumps/come down hard off things, etc.

Front -

For the front...because you swing the tire inward and outward to steer...and because the two ends don't affect each other...its a different ball game.

For X's, the rear of the front tires hit the rear of the wells on turns, and even on compression...especially if turned, etc.

One side drooping doesn't impact the other side stuffing...BUT, each tire swings through its OWN arc, up and down.

The difference is that the arc is truncated by the bumpstops, so the compression limit is not whacking as much to the inside, as it is upwards, at the fender, or well top.

So - adjustment of the turnstop bolts to prevent rub on full lock is required... when the tire's end is turned INWARDS.

BL/SL -

For uptravel...again, cutting off the parts in the way, or doing a BL is required.

33's fit nice with a 2" BL...as a 2" BL generally brings the wells up enough for a 4" larger diameter tire to stuff.

A SL can't do that for you, as on compression, the tire stuffs to the same point...with the caveat that it DOES have further to go to get in there...so you CAN get away to a point, just not all of it.



Same with a PML - at ride height, there's room for more rubber...but on stuffage...not so much.

So - really, the job of a BL is to fit larger tires.

The job of the SL is to get ground clearance, and articulation.

The job of the larger tires is to lift the ENTIRE truck, gaining ground clearance for the diffs too, etc...and, to improve traction, and flotation, so you don't get stuck as easily, etc.

So - they all go together towards a common end.

Each helps the other, and the truck, do its job.



PS - I thought the stock alloys had 5.5" of BS.

I'm running 305/70/16's, which are a little fatter treaded, and a little taller, than the same tire in a 33x12.5/15...on the stock 16x7 alloys.

I used a 2" BL to make room, adj the turn stops to stop rub at full lock, cut off a small strip of plastic where the front mud flaps used to mount, and did a 3" SL.

I did essentially no trimming, and it all works.

When I added the Revolvers...due to the extra droop/travel...the rear tires started rubbing on full stuff/droop compression, with the compressed tire against the frame...not bad, but enough to passionately kiss the Lift Lips.

They are getting a little chapped now.

Anyone have pics of 33's on a 8inch wide and 5.0 backspaced rim?

This is my X with a 2" BL and PML. The tires and wheels are Cragar 342's (6 on 5.5 with 4" BS) and tires are BFG AT/KO's 33x12.5x15's.

How much do they stick out?

I'd guess an inch or so...like in the pics.

I have 33/12.5's with 4.75BS and mine stick out about 3~3.5"
He has a BS of 4, I'm betting his stick out about 4~4.5"

I think his would stick out less than yours, remember the more backspacing the less the tire sticks out.

Hey TJ how do you think the truck would be if it had 33's on and 8in rim and 4.5BS with a lift like ours? Minior rubbing?

Right, I have more than his, so mine stick out less, thats what I said

4 sticks out more than 4.75

Unless I'm Lex-ing out again...the 8" rim sticks out about a 1/2" more than the 7" rim....add in one less inch of BS for the 4.5 BS - and that's about an inch and a half further out.

So it would hit for sure on straight compression, and swing out quite a bit wider in its arc....so yeah.

The rear would clear the frame side better stuffed, on opposite side stuffage/droopage situations though.

You could trim more...and turn out the turn stops all the way...but your turning radius will be a bit Queen Mary-like.

My 305/70/16's are a bit taller than, and a bit wider treaded than a 33x12.5/15 of the same tire...and on a 5.5" BS rim, they tuck easily...but, want to nibble at the frame side too.

I could space them out maybe an inch before they'd hit too much....which would make a 4.5" BS at the fender line...and arc into well stuff up front.

If I left the BS at 5.5", and went to an 8" rim...I might JUST make it...If I did both...I'd be hitting left and right.

Its one of those issues I'm wresting with...I'm strongly considering a set of 33x13.5/16 LTB's as play tires...same 1/2" to play with.

Oops i thought you has 3.75 BS my bad

I dont think that my tires would come even close to hit on straight compression, my suspention is too stiff in the rear.

Really? Too stiff to compress?

That's bad...it makes you less stable, as it tips you over to the other side if you can't compress.



I have a Deaver 3 pack AAL, AND a Calmini 2 pack AAL, interwoven with the oem leaves (A progressive 8 pack...)...and I can STILL fully stuff.

What's the dileo on your suspension?

Hmm i have the Ac 3pack AAL. Maybe im wrong, I guess it does stuff but i never get a chance to see it lol but when would the truck do a straight compression both tires comming up into the wheel wells?

Here is another view straight down the body of the X with the tires sticking out. It is about 1-1.5 inches sticking out with 4" BS.

But, if you ask me it looks good!



On a side note, with less backspacing (further out it sticks), you will start to get the rooster tail along the side of your truck. I am starting to notice that with the snow melting around here and the ice on the roads turning to slush.

it adds character

When you finsish that jump of course...



Or are coming down off of a ledge...or are starting UP a steep obstacle, etc.

Luckily, MOST of the rear stuffage is one tire at a time though.

In many states, such as New Jersey and its Reichstags, it is illegal for your tire to protrude past the well/fender....we have to install fender flares to be sure the tire is always in the shade, etc.

It looks good. When i get new tire and rim combo i think ill stick with 33's but on a 8in. rim and 4.5 backspacing. So it will only stick out a bit an inch and a half.

You do know that you live in NJ, right?



Can't stick out...they'll fail your ass.

Gotta tuck in NJ...that's the law son.

Ill throw the stock rims on for when i go to get an inspection