37s on stock Sasquatch! What ACTUALLY rubs? [video]

[PTTyler]

How much lift for 37" tires is probably the most over-asked question in any Bronco forum so I made a video to address it. I would love feedback and for you to share it with anyone else asking this question so they understand WHY lifts do not let you fit bigger tires!

The main questions that I wanted answered for myself are:

1: If you put 37s on a stock Sasquatch suspension, what ACTUALLY rubs? - I put our stock Sasquatch Bronco on a forklift to flex it out after putting the 37s on.
2: If you remove/replace the crash bars, are there other clearance issues with 37s? - I installed a JKS max tire clearance kit which is the minimum necessary mod
3: Can one video finally put an end to the question: What size lift do I need to clear XX" tires? - I made a rudimentary suspension model to demonstrate why a lift has very little correlation to the tires you can run. Hint: if you rub at full bump at stock, you'll rub at full bump with a lift (depending on the type of lift)

This is part one of our build series. Next is installing an Icon stage 5 lift. Spoiler alert: I've already been driving and wheeling on it for a few months.



I don't pretend to be a suspension expert but I have been trying to learn as much as I can so it would be great if this became a bit of a Q&A about lifts and tire sizes, whether Bronco specific or not. And if I don't know the answer to something, I have plenty of people I can ask.

By the way, I'm running a Mickey Thompson Baja Boss M/T 37x12.5x17 on a Mayhem Wheels Convoy 17x9 -6 offset +4.76 backspace

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[Valhalla]

Hi, I'd like to add if I may, when you lift the articulation of that lift comes in to play for rub. You may need to lengthen your bump stops. This is often overlooked.

I run a 3" body lift and 37x12x17 interco sxII they are on Hutchison Rock Monsters.. I rub dricersside cutting left at compression slightly. I run the stock squatch tires on highway.

 

[lakesinai]

How much lift for 37" tires is probably the most over-asked question in any Bronco forum so I made a video to address it. I would love feedback and for you to share it with anyone else asking this question so they understand WHY lifts do not let you fit bigger tires!

The main questions that I wanted answered for myself are:

1: If you put 37s on a stock Sasquatch suspension, what ACTUALLY rubs? - I put our stock Sasquatch Bronco on a forklift to flex it out after putting the 37s on.
2: If you remove/replace the crash bars, are there other clearance issues with 37s? - I installed a JKS max tire clearance kit which is the minimum necessary mod
3: Can one video finally put an end to the question: What size lift do I need to clear XX" tires? - I made a rudimentary suspension model to demonstrate why a lift has very little correlation to the tires you can run. Hint: if you rub at full bump at stock, you'll rub at full bump with a lift (depending on the type of lift)

This is part one of our build series. Next is installing an Icon stage 5 lift. Spoiler alert: I've already been driving and wheeling on it for a few months.



I don't pretend to be a suspension expert but I have been trying to learn as much as I can so it would be great if this became a bit of a Q&A about lifts and tire sizes, whether Bronco specific or not. And if I don't know the answer to something, I have plenty of people I can ask.

By the way, I'm running a Mickey Thompson Baja Boss M/T 37x12.5x17 on a Mayhem Wheels Convoy 17x9 -6 offset +4.76 backspace

I was told early on--when I was researching tire and wheel sizes--by a Ford engineer that the related question to fit and rubbing is the suspension geometry. What lateral forces does an upsized tire&wheel put on drivetrain and suspension components that it was not designed for? In my case, we were discussing "0" offset wheels on a non-sas axle. It might be made to "fit", but without corresponding UCA'S and coilovers, it might add stress that could prematurely wear out components. I don't have the knowledge, but since you invited open discussion, I thought I'd note that "fit" is not the only parameter.

 

[techdisaster]

This really timely for me. I’m going to 37” tires by spring of next year. I went with a -12 off set for my wheels (Reika Ramblers) and I’m thinking of the same tires you use.

 

[PTTyler]

I was told early on--when I was researching tire and wheel sizes--by a Ford engineer that the related question to fit and rubbing is the suspension geometry. What lateral forces does an upsized tire&wheel put on drivetrain and suspension components that it was not designed for? In my case, we were discussing "0" offset wheels on a non-sas axle. It might be made to "fit", but without corresponding UCA'S and coilovers, it might add stress that could prematurely wear out components. I don't have the knowledge, but since you invited open discussion, I thought I'd note that "fit" is not the only parameter.

Right. And adding a lift just compounds that. There are material and engineering limits to the factory suspension and drivetrain components. Everything was engineered by Ford for around a 33-35" tire at the factory height. Adding weight adds stress to components. Adding lift adds stress to these components.

Let's stick with the factory suspension geometry and factory wheels but increase the tire size. Not only do we increase the weight, but we also increase the contact patch or the amount of rubber touching the road. As far as suspension goes, components would wear out faster, but I personally don't think it would make too much of a difference over the life of the vehicle. The UCA sees relatively little stress overall and mainly acts to keep the spindle upright. I don't think the added weight of the tire would affect the LCA much as the LCA is designed to support the sprung weight of the entire vehicle. The coilover will need to act against more moving mass but I wouldn't worry about it as a wear item.

My biggest concerns would be the tie rod and axles. This is what we see most often as the weak point on these and other IFS vehicles. These two components have energy added to them from the diff and the steering box and the tire resists this energy. So added tire weight and friction from the ground are both working against them.

Going from a +30 to a 0 or -12 offset wheel further compounds these forces acting against these components.

Long story short, yes, fitting 37s has no relevance to amount of lift but does need more consideration than just clearing out the wheel well.

 

[PTTyler]

Hi, I'd like to add if I may, when you lift the articulation of that lift comes in to play for rub. You may need to lengthen your bump stops. This is often overlooked.

I run a 3" body lift and 37x12x17 interco sxII they are on Hutchison Rock Monsters.. I rub dricersside cutting left at compression slightly. I run the stock squatch tires on highway.

Where are you rubbing? did you lengthen bump stops? I would have thought a 3" body lift would have been fine for upper fender clearance without limiting up travel. But the body lift doesn't alter clearance with the frame and frame horns.

 

[Valhalla]

It's the front crash bar holder.. Only seems to rub the drivers side though.. it is slight.

 

[PTTyler]

This really timely for me. I’m going to 37” tires by spring of next year. I went with a -12 off set for my wheels (Reika Ramblers) and I’m thinking of the same tires you use.

You're definitely going to rub unless you limit uptravel. With -12 wheels, I also had to remove my fender liners.

I love these tires but I do wish I went with the Baja Boss A/Ts for the amount of road driving I do. The M/Ts handle fine and are quiet for a M/T but you can hear a slight hum above 65mph. I run them at 35 psi on the hwy.

 

[diggingdirt1]

Bone Stock 23 Badlands SAS, 37/12.50 Nitto Ridge Grapps. Slight rub at full lock on inside frame rail Nothing Major at all IMO. Wife everyday drives it randomly drives over curbs among other things. I like the Stuffed tire look personally. Works for us.

 

[Valhalla]

How does it do offroad.

 

[diggingdirt1]

How does it do offroad.

I’ve got a Raptor for that lol

 

[Valhalla]

So you bought a rock crawler for the mall?

 

[Midnight_Blue]

This is part one of our build series. Next is installing an Icon stage 5 lift.

So a lift isn’t necessary, although 37’s will rub, so you’re adding a lift but telling us that a lift isn’t needed, is that right?

 

[Lil Mul]

Thanks for the new T-shirt idea !

" See what rubs. Cut anything that does ! "

 

[popo_patty]

Hey I did one of these awhile ago

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