[ScaldedDog]

I've had 35' MTR's for awhile, and would like to move up to 37's in the spring. While I really like wrenching on my rig, I don't like mixing wheeling and wrenching , so I'm planning the upgrades I need to do to prevent preventable breakage. I'm likely to go with MTR's again, but may choose something a little more aggressive (e.g. Krawlers, 12.5" wide TSL's). I probably won't do something like 15" wide SX's.

What reasonable upgrades are necessary to minimize trailside wrenching, as well as the chance my new tires will end up pointed at the sky?

Current rig

88 4Runner (about 4500lbs?), old-style longs on stock inners up front, stock IFS axle in back. Mildly tuned 3.0 V6, dual cases with 4.70's in the rear, 4.88's in the diffs. Plenty high enough for me, already, so I'll carve sheetmetal 'till the 37's fit.

What to do up front?

Width - I'd like to go a little wider with the taller tires, but I'm already running 1.5" spacers. (The kind that bolt to the rotor with the stock wheel studs, and have their own studs for the wheel.) I've got aluminum 15x8" wheels with 3.5" backspacing (IIRC). I could go with a 10" wheel, but I like the way the 8" ones have held beads.

Beadlocks - With the taller sidewall of the 37" tire, am I more likely to pop beads than with the 35's? (It seems so to me, but I've not run them, yet.) If so, I could have my current wheels beadlocked, or buy a set from a guy on this board that lives near me (Here's a plug for you, Jeremy!) Do beadlocks (Champion's, I assume) make aluminum wheels effectively wider, like Rockstomper's do with steelies? If so, that might be just the ticket.

Axle strength - I'm fairly light on the throttle, most of the time, but it is a 4500lb rig with a 200:1 crawl ratio. Do 37" tires "require" an upgrade to chromo inners?

What to do in the back

Width - I have a set of 3/4" spacers I took off the front (the kind that just use longer studs to to hold on both the spacer and the wheel). Could I safely run those in back, or is that just an invitation to lose a wheel?

Axle strength - I never worried about breaking a rear axle, but I'd sure rather have a full floater if one did break. Trouble is, it's the guys I know that have full foaters who're always breaking them. (Mostly Warn hubs on Jeeps, though.) How many of you have broken stock IFS rear's? What size tire were you running when it happened?

All opinions are welcome, but those based on experience are more valuable.

Mark

 

[RE:Todd]

85 Runner, 174:1, ARB Hi-pinion front, spool rear, 4.10's

Front. I run 37 MTR's on a 15X8, never lost a bead. I've broken two long side and two short side stock inner's in a year and change. All have been broken in really bad bind spots, I do have a set of All-Pro 4140's to go in when I break another.

Rear. I've broken 2 rear axles in an IFS rear. Replaced with Chromo's from All-Pro, no issues. Did strip one R&P, bending the spool at the same time.

If I were you, I'd go with beadlocks (I still need them) and wheel what you have. Buy a set of chromo's all the way around and replace as needed.

 

[Dustin]

Sounds like you know the answers to most of your own questions. I think a taller tire with more sidewall makes a tire LESS likely to debead. Champion beadlocks don't make a rim wider because they machine the old bead off and weld on a new inner ring rather than welding the inner ring to the old outer bead like the diy beadlocks do. The new 37" radial irok's are already out and might be something to consider.

 

[ScaldedDog]

Sounds like you know the answers to most of your own questions.

Lots of thought, but not a lot of answers. With unlimited funds, of course, the answers would be easy...

I think a taller tire with more sidewall makes a tire LESS likely to debead.

Ummm, I hadn't thought of it that way, but I can see how that might be the case.

Anyone have any thoughts about the spacers in back? That's a dirt cheap thing for me to do, but I don't want to *decrease* reliability just because I can.

Mark

 

[chad dillon]

How about some wheels with around 2" backspacing? Reversed rims will also help keep the bead on.

 

[RE:Todd]

Anyone have any thoughts about the spacers in back? That's a dirt cheap thing for me to do, but I don't want to *decrease* reliability just because I can.

Mark

What's wrong with your current width?? If your going beadlocks with new wheels, change the backspacing, if you're that worried about the width. I've got the IFS rear in mine, width is fine for the 37's and the ride height.

 

[Dustin]

Can you cut out a littl more body and lower the suspension an inch? That would give you the same ride height you have now with the bigger tires. Then you have no added instability and no need to run the spacers. Personally I don't see any real problem with them in the back. Carry a few extra stock wheel studs with you. They are easy to replace if by some chance you do break the long studs on the trail which I don't really see happening. Carry a spare stock shaft for the rear and see if you break anything. I never did running 38"sx's on my old pu.

 

[ScaldedDog]

What's wrong with your current width??

Actually, it's pretty good right now. Whenever I do anything that makes it taller though, I try to go a little wider at the same time. I've done that on a couple of rigs now, and it works out well.

Mark

 

[ScaldedDog]

Can you cut out a littl more body and lower the suspension an inch? That would give you the same ride height you have now with the bigger tires. Then you have no added instability and no need to run the spacers.

I might do that. I may just run the spacers though, (since they're already sitting in the garage) and be done with it.

I already carry spare inners, so adding a rear wouldn't be a big deal. I assume I'd need the bearing, too, since it'd probably get mangled if the shaft broke. Correct?

Mark

 

[RE:Todd]

I might do that. I may just run the spacers though, (since they're already sitting in the garage) and be done with it.

I already carry spare inners, so adding a rear wouldn't be a big deal. I assume I'd need the bearing, too, since it'd probably get mangled if the shaft broke. Correct?

Mark

I carried mine assembled without the backing plate or brake stuff. Pull the broken, slide in the new shaft and bearing assembly, plug the brakeline, throw on the drum (proper compression for the studs and wheel), install the wheel and go.