Minimum lift to run 37's??

[Rockcrawler]

I'm considering 37" BFG all terrains for my next set. I suspect the rear of the front fenderwell is the limiting factor due to my 315 experience. I almost never kiss them now with my truck, even pulling into a drive which forces articulation etc.



Power is not an issue, When I'm towing I'm well over 2000rpm and often wish I had another gear anyway- I don't tow over 10k.



so can I get away with 2" in front, or will it take 3"



I'll stick with the 315's if I have to, don't want to buy a 4" system for a dedicated tow rig.

 

[Doubleclutch]

Kent Kroeker runs 37's on his T-Rex truck. Seems to me he talked about carving some fender to aid the installation. Look up the "My racing suspension is here!!!" thread. The T-Rex lift is about 2".

Greg

 

[DOUGMartin]

I was thinking of going with big tires and using air bags to lift the truck to drive and lower it so i can get my fat arse in it lol. I know it sounds like over kill but might be nice.

 

[XJSuperman]

37's would fit the rear without a lift... you may not have a lot of "flex" room but if you don;t do any serious offroading where your suspension fully cycles this would not be an issue.

As for the front... the 35's (34. 5") fit mine with NO lift and no rubbing. . so 37's should fit with a 2" lift on the front and the rear stock.

 

[XcumminsX]

37"s Dont fit with a 2" lvl kit.

 

[Kurt Henzler]

rockcrawler, you said you did not want to lift your truck with a 4 inch system for towing purposes. do you think it would be a problem even with a good lift like super lift, or one that gives all the components to do it right. the new arms , springs, shocks, pitarm, drop lever. do you think towing will suffer with a lift. i want to level my truck , maybe go with 305's, but can not decide and the correct way.

 

[blake underwood]

I ran 37 MTR's w/a 2" coilspacer, won't rub unless you REALLY TRY HARD. The key is to use stock wheels. I ran 'em in the dunes for the whole weekend and only rubbed one time. And I wasn't pus*y footin' around neither.

 

[XJSuperman]

Nick... how do you know?? You ever tried??

I remember reading here that some actually DID it. . and either way if 35's fit with NO lift then it's very safe to say 37's would fit with 2". The extra tire clearance needed is ONLY ONE INCH... . I have that much clearance with my 35's now without a lift at all.



You take tire RADIUS into account when looking at clearance... from the wheel center a 2" larger tire will only net you 1" extra at any given spot on the tire... the 2" is TOTAL tire height.



I have said before each truck is a little different... some are rubbing with 35's others are not... so don;t say something will NOT work or say 100% that something will work. . because you can't. . and neither can I. I was told by many that with 35's I;d need alift... but I don;t.



The 37's SHOULD fit with just a 2" level up front... for everyday driving and even mild to moderate offroading 3" should be the most needed BUT may not be necessary.

 

[XcumminsX]

Yes i did try 37 inch tires. With the 2" spacer up front it rubbed on the arm. Looked awesome but didnt function right... Im willing to bet this will end up at the factory set-up again. . Some trucks have better tolerances than others.



Nick

 

[XJSuperman]

If it rubs the arm only at full steering lock most folks can tolerate it... and as you and I both said... the factory tolerances may allow some to do it. It may not have 'worked' the way you wanted or expected but may be fine for someone else.

 

[Rockcrawler]

I'm willing to tolerate arm rubbing at full lock- I'd tweak my stops. I'm more concerned about the fender behind the front wheel.



XJ- no offense but your thinking is a little off. Two inches of lift helps mostly the up clearance. The problem is 90 degrees from "up" and rearward of the front wheel. so it's not black and white. I guess I'll have to mount a 37" BFG Krawler from the comp buggy and see what happens with the chassis on jack stands to simulate a 2" lift in the front.



I do know factory wheels are better suited to this but they are long gone and not coming back.



Kurt, I tow long and hard at 77-82 mph, I want the highway handling of the truck to be all it can to an extent. spending the cash and raising the CG 4" + the extra tire height is not something I'm willing to due simply for the cool factor of 37's vs 315's which are on it now (Unless I can start finishing in the money and come up with some disposable income).

 

[turbojet]

This goes back to doing it right or not.



It depends on what you want to accomplish. If it's just looks or function too.



Do you want to rub some of the time, all the time, do you wheel, do you want more suspension travel?



My dually has 37s and I put on the superlift 6" kit. No matter how hard I wheel, they don't rub, plus I wanted the right look with that size tire, I didn't want the stuffed tire look. But that's me and doin it right always costs more money. You could run 40s with only cutting sheet metal too.

 

[TBrennan]

Just curious why so many seem to prefer the Superlift over the Skyjacker?



The Superlift uses blocks in the back and the Skyjacker uses an add-a-leaf which I always thought was better.





Is there any component of the Superlift that makes it better than the Skyjacker?

 

[Rockcrawler]

Another point of view- right is relative, I suspect we all really agree on that. If you're going to wheel your truck hard, and that means lots of articulation to you then you need more lift to make it all work right.



Rubbing lower control arm is not going away unless you redo your arm mounts or make banana arms. It's hard to call banana arms "right" they fold, especially if wheeled hard. I'm not ambitious enough to move arm mounts so I can have straight arms.



For the towing and light offroad I do at race sites my current setup is "right" for me, almost never rubs and chances are reasonable that I could pull off the 37's with 2" in front.



Looking "right" is completely subjective- if it makes you smile, great.



with a 2" spacer the only thing I consider hokey is the lack of adjustment for the track bar. other than that you tweak your shocks for the longer length and realign the front end.

 

[XJSuperman]

No offense taken Rockcrawler... but my thinking is not off... I might not have been very clear. I have looked at all possible clearance issues on the front of my truck... which for all intents and purposes is similar to everyone elses with the exception of "factory tolerances" mentioned above.

CLearance is looked at with the entire fenderwell taken into account. . front, upper, and rear as well as the inside 'inner fender' and the lower front fascia/bumper airdam AND the control arms. Sorry if I was not clear on my thinking but I do understand. You also have to take into account the 'arc' motion of the suspension... the wheel center point will travel in an "arc" from the pivot point(s) of the conrtol arms. . so technically the wheels and tires don't move straight up and down... there is a curvature to the movement ... when moving up they essentialy move up and back and when moving down... down and back.



And other ways to get the tires off the lower arms is to change wheels... figure out the amount of backspacing you would need ... less BS would get the wheels and tires alittle farther outboard thus compensating for the extra tire dia hitting the amrs.

OR... make the steering stops extend just enough to where they don;t allow the tires to rub the arms at full lock... it stinks that our front ends don;t have the steering stop adjusting bolts like jeeps do. . makes it easy.



Either way we are thinking along the same lines as your last reply states what I have said from the beginning.

 

[RKinman]

Why don't you guys take some pics of the clearance at full-lock both directions and centered with the different tires? THat way it will help everyone.

 

[Spooled-up]

Like XJSuperman said...

Wheel offset if very critical on our trucks. Also the width of the wheel can make or break a wheel/tire/lift combo. If you use a narrower wheel, the overall width of the tires is less allowing more clearance for the fender. This of course depends on offset of the wheels. The more + offset, the more "tucked in" the tire will be into the wheelwells. This also puts the tire closer to the control arms.



According to National Tire and Wheel's Tire fitment guide, in order to run a 37" tire, you need a 5-6" lift. They of course do not say what width of tire, what offset, what width of wheel. They only state that 4. 5" of backspacing will stick out of the fenders.



I guess the only way to truly tell what would work would be to try different combo's on the truck and articulate the suspension.



That show "Trucks!" had a gadget you could mount a tire to and then mount it on a truck. You could move the tire in and out to simulate different offsets and you could make the wheel wider or narrower to see what would work. A search of their site revealed nothing.

 

[turbojet]

I prefer blocks so I can keep my stock helper springs and ride in the back.

Originally posted by TBrennan

Just curious why so many seem to prefer the Superlift over the Skyjacker?



The Superlift uses blocks in the back and the Skyjacker uses an add-a-leaf which I always thought was better.





Is there any component of the Superlift that makes it better than the Skyjacker?

 

[turbojet]

Rockcrawler,



No one needs to tell you what you like, I understand.



I have worked in off road shops and there is an industry concept of tire size and clearance on OEM vehicles being lifted and tire fitment. I can tell you that there isn't one shop or lift manufacturer that won't advise you against 2" of lift with 37s on that vehicle. I talked to superlift and a few other places before making my decision. It isn't a free for all, there are guidelines. I am confident that if I had only 2" of lift on my truck I would already be grinding sheet metal at the rear of the fenderwell



Before I did this set up I had 315R70s on for a while with a 3" spacer and I had about 1/2 to 3/4 inch clearance at the rear of the fenderwell at closest turn point

 

[Punkineater]

I prefer wheelwell clearance and like my tires and wheels wide. If I was going to run a 37" tire it would be a wide one and I would settle for nothing less than 8" of lift. I woudn't think of running 37's with a 3", 4", or even a 6" lift. But then again that's just me and everyone has different tastes and preferences with their setups. It's your truck and you ultimately have to live with your design so, as long as it's safe, experiment and have fun.