I found a great deal on some MTR in 38 and want to know if my setup 850J and 30mm spacers in the front, and 863 and 30mm spacers in the rear. The real question is bump stops.
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How do I go about fitting 38s
- Thread starter OffRoadScott
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How much uptravel do you want?
What 38s were you wanting to run?
What 38s were you wanting to run?
- Thread starter
- #3
They are Goodyear MTR in 38x14.5x17.
I know that I will have to add to the stock bump stops, but how much? I am also concerned about the turn in with the 14.5" wide tires.
suspect that'll take some cutting or BFH on the width with the scrub radius.....but love to see it ! someone need to pioneer these things....
Maybe a body lift?
- Thread starter
- #6
I am not keen on the idea of a body lift, there is enough body roll already and I don't need to raise the center of gravity anymore.
@Box Rocket maybe you can add some insight into this. I know you are running 37's, but my question is how much bump stop would you recommend?
A body lift wouldn't raise your center of gravity as much as a suspension lift. I would put the lift on and then check for clearance to determine how much to add to your bump stops. As far as turning, It all depends on the backspacing of your rim
I would agree. It's only raising the body 1", the frame, drivetrain, axles, etc all stay where they currently are.
I think the 14.5" width will be your biggest obstacle. Are you running fender flares?
The traditional method for experimentation for things like this is to mount up the tires, jack up one corner at a time and see what rubs. Note where it rubs, then sawzall that bit off. Rinse repeat. Not sure if goodyears are true to size, but with the number of people running 37's, I would guess diameter will not be a big issue, but the width will be your main challenge. May have to experiment with spacers and different wheels, or just cut a lot.
Yeah 14.5 wide is a little rough. 315/75r16 that a lot of people run is 12.5 in wide so as long as your wheel has a little more offset (less backspacing) you can probably get away with it.
I have 38's, no cutting, but you need a decent lift for the fronts not to rub.
If you could move the front axle forward about an inch, or do the mod to move the bolts on the radius arms forward on the mounts. I should probably have done that by now myself.
I've got airbags, and am not sure at what height lift equivalent it would be at. In cab controls, i get a bit of rub sometimes with them.
If you could move the front axle forward about an inch, or do the mod to move the bolts on the radius arms forward on the mounts. I should probably have done that by now myself.
I've got airbags, and am not sure at what height lift equivalent it would be at. In cab controls, i get a bit of rub sometimes with them.
I'm running a 365/75R16 (37.5 x 14.3). 3" body lift, no suspension lift. Stock wheels. Issues you will run into due to the width are reduced turn radius, heavy rubbing in the front wheel well, and rubbing in the rear wheel well.
Reduced turn radius and front wheel well rubbing are interdependent. Factory wheels are 0 offset, it you push the wheels out to eliminate the tires rubbing on the radius arms, it is going to exacerbate the tire getting into the rear of the front wheel well. I accepted the reduction in turn radius, and 99% of the time it isn't an issue. Adjusted the steering stops out.
As for the front wheel well rubbing, I trimmed it out. I think there are pictures in my "build thread" in my sig.
The rear wheel well rub is what it is. Rubs the paint off, but does no damage to the tires or truck, and there really is nothing that can be done.
Reduced turn radius and front wheel well rubbing are interdependent. Factory wheels are 0 offset, it you push the wheels out to eliminate the tires rubbing on the radius arms, it is going to exacerbate the tire getting into the rear of the front wheel well. I accepted the reduction in turn radius, and 99% of the time it isn't an issue. Adjusted the steering stops out.
As for the front wheel well rubbing, I trimmed it out. I think there are pictures in my "build thread" in my sig.
The rear wheel well rub is what it is. Rubs the paint off, but does no damage to the tires or truck, and there really is nothing that can be done.
- Thread starter
- #13
Yes but I am open to trimming or removing them. It would make rattle canning the LC a lot easier.
i am running 37s MTRs on a 4" lift. Tons of trimming on the flares and fenders to make them fit for rock crawling without rubbing.
I am running 17 x 8.5 w/ 3.25 BS
I am running 17 x 8.5 w/ 3.25 BS
- Thread starter
- #15
i am running 37s MTRs on a 4" lift. Tons of trimming on the flares and fenders to make them fit for rock crawling without rubbing.
I am running 17 x 8.5 w/ 3.25 BS
With all the input and the idea of trimming s***, I think I will probably just go with 37s.
Late to the party but the bigger issue with the 38's is the width, not the diameter. That wide of a tire is what will cause most of the rubbing. The diameter would probably work fine with minimal effort.
My personal approach is to use as small a bumpstop as possible. Trying to get a well balanced suspension only to limit the compression isn't ideal so I try to keep as much available suspension travel as I can with minimal bumpstop modifications. Bumpstops should be set to keep the shocks from bottoming out as the priority, and thats going to be a little different for everyone with so many different coil and shock configurations out there. This might mean more sheetmetal trimming to make it work the best and not rub tires.
If you're not concerned about suspension travel, then you can use larger bumpstops to keep the tires out of the fender sheetmetal first. but it might be limiting your compression.
Heckraiser did a pretty good job of describing a good way of checking clearances. If you have access to an RTI ramp anywhere close to you, it works well for checking clearances. This is the only practical use for RTI ramps. The thing to make sure to do is turn the front tires lock to lock. Compression with the tires straight might clear fine, but won't when you turn the tires while compressed.
As for body lifts.... I personally don't see any issue with a 1" body lift. I don't like body lifts larger than that, but there are a number of benefits to a 1" body lift. Besides some additional clearance for tires, it can also increase airflow under the chassis to the radiator. On the 80 it can provide enough clearance under the body to re-route the exhaust over the frame, rather than leaving it vulnerable in the original position under the frame. It won't mess up any suspension geometry. 1" is small enough that there is very little negative impact on center of gravity.
I have a 1" body lift. Just be sure to use quality kits when doing a body lift. Cheap ones can crack/break and cause some serious headaches if that happens. Like, DON'T use hockey pucks. haha. I've seen it done so you might laugh but someone thought it was a good idea. It's not.
My personal approach is to use as small a bumpstop as possible. Trying to get a well balanced suspension only to limit the compression isn't ideal so I try to keep as much available suspension travel as I can with minimal bumpstop modifications. Bumpstops should be set to keep the shocks from bottoming out as the priority, and thats going to be a little different for everyone with so many different coil and shock configurations out there. This might mean more sheetmetal trimming to make it work the best and not rub tires.
If you're not concerned about suspension travel, then you can use larger bumpstops to keep the tires out of the fender sheetmetal first. but it might be limiting your compression.
Heckraiser did a pretty good job of describing a good way of checking clearances. If you have access to an RTI ramp anywhere close to you, it works well for checking clearances. This is the only practical use for RTI ramps. The thing to make sure to do is turn the front tires lock to lock. Compression with the tires straight might clear fine, but won't when you turn the tires while compressed.
As for body lifts.... I personally don't see any issue with a 1" body lift. I don't like body lifts larger than that, but there are a number of benefits to a 1" body lift. Besides some additional clearance for tires, it can also increase airflow under the chassis to the radiator. On the 80 it can provide enough clearance under the body to re-route the exhaust over the frame, rather than leaving it vulnerable in the original position under the frame. It won't mess up any suspension geometry. 1" is small enough that there is very little negative impact on center of gravity.
I have a 1" body lift. Just be sure to use quality kits when doing a body lift. Cheap ones can crack/break and cause some serious headaches if that happens. Like, DON'T use hockey pucks. haha. I've seen it done so you might laugh but someone thought it was a good idea. It's not.
- Thread starter
- #17
So I am looking at two sets of tires, 38s and 37s both MTR. I have always liked the MTR tires. If I do get these tires I will have to sell my perfectly good KO2s.
Plus from what I found in the limited articles/threads people did bring something up, a added stress on the axles and differential. I know that 37s will do the same but people have been doing 37s longer and there are more positive results.
Plus from what I found in the limited articles/threads people did bring something up, a added stress on the axles and differential. I know that 37s will do the same but people have been doing 37s longer and there are more positive results.
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Just get the 37s. Pretty much tried and true at this point. The additional trouble of going with a 38" seems hard to justify.
I agree with @Bludozer , just go for the 37's. Will save you some headaches and some cash in the short term. Wide 38's would definitely demand a quicker need for axle upgrades etc.
MTR's are great tires. Easily one of my favorites for trail use, and good on the road too.
Scott, got to be honest. This is a deep deep rabbit hole to jump down - high effort - expensive.
Doing this because of "getting a good deal" on whatever tires seems like putting the cart before the horse.
Everything you have to do to make big tires work seems like the main point to consider - the tires themselves? relatively minor.
33s - pfft - nothing to it. Stock gears are still OK, a little weak but livable.
35s - Fits. Largest that fits without any real difficulty or major mods. The best practical answer for larger tires. Re-gear or be sad.
37s - Fits with effort. Has to be done just right. Right on the hairy edge. Easy to screw up and cost a lot. But - lots of good cases to learn from. Re-gear practically required.
38s and up - Your truck is a dedicated fab project. Major cutting required. Re-gear - of course.
So it seems to me.
Doing this because of "getting a good deal" on whatever tires seems like putting the cart before the horse.
Everything you have to do to make big tires work seems like the main point to consider - the tires themselves? relatively minor.
33s - pfft - nothing to it. Stock gears are still OK, a little weak but livable.
35s - Fits. Largest that fits without any real difficulty or major mods. The best practical answer for larger tires. Re-gear or be sad.
37s - Fits with effort. Has to be done just right. Right on the hairy edge. Easy to screw up and cost a lot. But - lots of good cases to learn from. Re-gear practically required.
38s and up - Your truck is a dedicated fab project. Major cutting required. Re-gear - of course.
So it seems to me.
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