Verifying > 33" tire clearance (for heavy off-road use)

[wfo9]

Question for those who have modified things to clear large > 33" tires.

I recently got 34s and cut and moved a bunch of things around to clear them. I started on the body mount chop today and decided to verify scrub angles and clearance after doing one side (passenger). So I took out the coil over and compressed one side to the bump stops. Clearance was actually great now at the body mount (in all positions). Full lock to passenger was also fine with just a tad of rub on the plastic liner, but full lock to driver rubbed pretty bad on the washer bottle (which I really can't move easily). If I back just a tad off the bump stop (.5 or so) everything clears). My question is how realistic is a full lock turn on the front bump stop on the trail. I can't think of a time when I have turned that hard on an obstacle (since I'm usually very aware of the stress on the CV joints....). I know I probably just need to get out and try it, but I was curious if others have attempted to verify clearance the way I did.

The question is weather or not I will actually experience rub on the trail without removing the washer bottle.

It seems so rare that I fully stuff a front tire (although it does happen I'm not sure if it is actually to the bump stop while crawling) and to be in a full lock at the same time seems unrealistic.

 

[Jeremy556]

I hit full stuff at full lock somewhat frequently, usually coming into a tight downhill switchback, especially if there's a ledge. I've found I rub the driver's side frame rail with the back of the tire when turning left.

Keep it mind you'll have some flex from the LCA bushings under real world circumstances.

 

[wfo9]

I hit full stuff at full lock somewhat frequently, usually coming into a tight downhill switchback, especially if there's a ledge. I've found I rub the driver's side frame rail with the back of the tire when turning left.

Keep it mind you'll have some flex from the LCA bushings under real world circumstances.

I was actually thinking about some trails in CO that I did last year being the most likely candidate for this scenario. Descending a long switchback trail down a mountain.

 

[CrazyNorwegian]

How close are you to rubbing on the back side? You could bring your caster down a little if you have the room.

 

[bimrunner]

I don't rub bad at full lock and stuff but my guess is that it is largely due to being able to set castor as far forward as possible. I'm over 5 on each side. If you ever go to a front bumper, you'll probably be able to get it set forward a bit more and give yourself that little extra clearance. Looks good fully stuffed though!!

 

[rochmpr]

Always plan for worst case senario. It may not happen often but when it does, you'll be glad you clearances. Murphy had the worst luck!

 

[wfo9]

Always plan for worst case senario. It may not happen often but when it does, you'll be glad you clearances. Murphy had the worst luck!

I think I'm going to have to remove the washer bottle before attempting really difficult trails that descend with switchbacks.... I'm generally always thinking about trying to get my wheels straight for tricky spots anyway, but not when descending.

I'm hoping to get it out soon for a shakedown run to get a feel for how probable the rub is.

I'm getting another bumper anyway... I was just hoping to run these tires in a few weeks at the LoneStar Jamboree.

It might actually get worse with an alignment. I've got the caster pretty far forward, but I would like to get more. I could go back a tad, but not worth the crappy road manners. .

 

[Jetboy]

I find that's usually when I blow up axles. For me that would be something like full lock - and then winch pulling 90* sideways against some obstacle. The winch compresses the front corner that's bound up to full bump stop. On my trail rig it's solid axle, so it doesn't matter as much but that's where I end up at full lock and full compression. Sideways winching.

For the rear rub, the worst is probably the situation of a tight trail at full lock and stuck with one corner compressed - like the switchback. Then trying to reverse out of it. That may flex your front into more rubbing. - This is where the reverse 8" clamshell is at its weakest.

 

[wfo9]

I just thought of another simple solution. Looks like I can space the bump stop out enough with a spacer. The stock bolt allows it to go out about .4. If that ends up not being enough in dynamic loads carry a couple of aluminum pucks and double sided tape with me to my shakedown run and slap them on until no rubbing.

 

[FactoryRide]

I just thought of another simple solution. Looks like I can space the bump stop out enough with a spacer. The stock bolt allows it to go out about .4. If that ends up not being enough in dynamic loads carry a couple of aluminum pucks and double sided tape with me to my shakedown run and slap them on until no rubbing.

Just move that windshield washer bottle! Mine is currently sitting in [MENTION=632]toyo[/MENTION] 's shop. You'll find that you will never need any more than when you don't have it haha. I keep a spray bottle now (Idea courtesy of [MENTION=89562]bimrunner[/MENTION]).

 

[wfo9]

I hit full stuff at full lock somewhat frequently, usually coming into a tight downhill switchback, especially if there's a ledge. I've found I rub the driver's side frame rail with the back of the tire when turning left.

Keep it mind you'll have some flex from the LCA bushings under real world circumstances.

I've also got some run on the driver side frame rail when pushing up a small obstacle in a full lock left turn. Its hell on the CV too (but I tested the awkward move in in 2wd). I think that is some bushing movement...

I'm going to stop screwing with it until I get it aligned and then go back and tweak a bit more.

Overall, clearing these tires seems to be a major PITA. I think I'll eventually get it worked out. It's obviously fine on the road.... Just requires lots of trial and error...

I'll tell you what though, even with the slight local testing I've done, it pops up on ledges much easier. Very noticeable difference in angle of attack. These are the biggest tires I have ever had on a vehicle. I see why people get hooked on 37+"... but as always, tradeoffs.....

 

[1engineer]

How about the new washer reservoir [MENTION=104049]marshal[/MENTION] is testing?

 

[wfo9]

How about the new washer reservoir [MENTION=104049]marshal[/MENTION] is testing?

I don't think that will work for my setup. I have my compressor for the lockers in that location at the moment (right behind the passenger headlight). However, I can just get a universal washer tank and pump and locate it somewhere handy... It wont have much capacity, but it will get the job done.

 

[marshal]

I don't think that will work for my setup. I have my compressor for the lockers in that location at the moment (right behind the passenger headlight). However, I can just get a universal washer tank and pump and locate it somewhere handy... It wont have much capacity, but it will get the job done.

Imo you should relocate your compressor

 

[wfo9]

Imo you should relocate your compressor

That's an option too, but I'll probably take the path of least resistance on the first attempt.

 

[harper7]

I've only rubbed the top of the wheel liner a a couple of times with 34's and that was hitting a washout at speed.No signs of rubbing the washer backside because I'm guessing you would have to have the wheels cut the whole way to the left,all the weight on pass side wheel and backing up .Even then,you might rub minor,so what.... tire will win over plastic and just push it forward with a rub mark.I've been on black bear switchbacks about 10 times and they are about as sharp of switchbacks as there are and still no rub there.

It's the metal inner fender that's part of the body and the rear frame rubs that would bother me more. That's why going bigger then 34's worry free is going to be a challenge without at least a 1/2" or 1" body lift. A small body lift is a better way to try and run 35's then cutting outer fender lips because use they'll still rub on the steel on the inside of the fenders.The inner fenders have a lot of accessories attached to them on the inside that would be hard to relocate if you cut them away.I'm happy with my 34's and setup now though.

Shrockworks makes a washer relocate for behind the airbox but I'd do like you said if I was going to get one and just by a generic smaller one,make a bracket and put it where I want as there's no real rocket science involved.

You can see rubbing on the top in this drivers side wheel well pic from last time at Gilmore and the steel inner fender I'm talking about right next to and behind it that's close. The pass side looked about the same but nothing on the washer bottle or remote res.

 

[wfo9]

I've only rubbed the top of the wheel liner a a couple of times with 34's and that was hitting a washout at speed.No signs of rubbing the washer backside because I'm guessing you would have to have the wheels cut the whole way to the left,all the weight on pass side wheel and backing up .Even then,you might rub minor,so what.... tire will win over plastic and just push it forward with a rub mark.I've been on black bear switchbacks about 10 times and they are about as sharp of switchbacks as there are and still no rub there.

It's the metal inner fender that's part of the body and the rear frame rubs that would bother me more. That's why going bigger then 34's worry free is going to be a challenge without at least a 1/2" or 1" body lift. A small body lift is a better way to try and run 35's then cutting outer fender lips because use they'll still rub on the steel on the inside of the fenders.The inner fenders have a lot of accessories attached to them on the inside that would be hard to relocate if you cut them away.I'm happy with my 34's and setup now though.

Shrockworks makes a washer relocate for behind the airbox but I'd do like you said if I was going to get one and just by a generic smaller one,make a bracket and put it where I want as there's no real rocket science involved.

You can see rubbing on the top in this drivers side wheel well pic from last time at Gilmore and the steel inner fender I'm talking about right next to and behind it that's close. The pass side looked about the same but nothing on the washer bottle or remote res.

That was really the root of my question. What methods do people used to verify clearance vs trial and error on the trail. It's not as easy as it sounds..

The only technique I could come up with was taking out the coil over and trying all steering angles at different points in the up travel to the bump stops. At the bump stops being the most obvious point of contact potential.

The alignment (mainly caster) is going to have a big impact... but then out on the trail there will be some other dynamic conditions at play.

I'm probably being a bit too anal about it... I was just trying to avoid the situatoin where I drive an hour (or even more) to a "legal" trail and find out my truck is not setup properly (done that before and its a real bummer).

 

[rochmpr]

That was really the root of my question. What methods do people used to verify clearance vs trial and error on the trail. It's not as easy as it sounds..

The only technique I could come up with was taking out the coil over and trying all steering angles at different points in the up travel to the bump stops. At the bump stops being the most obvious point of contact potential.

The alignment (mainly caster) is going to have a big impact... but then out on the trail there will be some other dynamic conditions at play.

I'm probably being a bit too anal about it... I was just trying to avoid the situatoin where I drive an hour (or even more) to a "legal" trail and find out my truck is not setup properly (done that before and its a real bummer).

At the rear of the wheel well, I beat the seam with a BFH and bent it over, towards the outside and cut out part of the plastic liner in this area. Sealed up the seam and sprayed with some undercoating. Also cut of the area in yellow in the pic.

 

[Miguelon]

I think I'm going to have to remove the washer bottle before attempting really difficult trails that descend with switchbacks.... I'm generally always thinking about trying to get my wheels straight for tricky spots anyway, but not when descending.

I'm hoping to get it out soon for a shakedown run to get a feel for how probable the rub is.

I'm getting another bumper anyway... I was just hoping to run these tires in a few weeks at the LoneStar Jamboree.

It might actually get worse with an alignment. I've got the caster pretty far forward, but I would like to get more. I could go back a tad, but not worth the crappy road manners. .

I got tired of hitting the washer bottle, so I got with Shrockworks. They offer a washer bottle relocation kit that upgraded to a metal washer bottle.