Hey y'all,

after tragically losing my beloved and pampered 06 F-250 to a completely cracked through frame after an interstate accident (not my fault) a couple months back, I am now, while fighting with the insurance companies, trying to make up my mind on a way forward.

My 06 had 35x12.5R18 Nitto Trail Grappler M/Ts on it and never had any issues with it, but also never towed anything heavy with it, never more than 15k lbs.

I have my eye on a 2016 F-350 SRW with the 6.7L diesel & 3.55 electronic locking rear axle. It's currently sitting on stock tires with 18" rims, but I would like to go to a new set of Nitto Trail Grappler MTs again in 35x12.5, either on the stock 18 rims or on the OEM 20" rims.

Does anyone here run this combination and have any experience towing 15-20k lbs with it? Any ideas whether the 18" or 20" rims will be better under the same 35" tire size?

I see on Nitto's site that the 37x12.5R20 can carry more weight than the same size tire in a 35" diameter. Does anyone here run 37" on a stock 2011 or up? The one I have my eye on has the snow plow pre package because it will get one of the heavy Ranch Hand Bumpers again with front trailer hitch and I will put a leveling kit in the front, but not sure that's enough clearance to fit 37s?

Any thoughts are appreciated.

 

I am not pulling a 20k pound trailer, but I did gross just under 21k lbs this summer on a trip to Ouray, Colorado (pic below is not Colorado). Even with 37x13.50x20 tires it pulled perfectly. We drove up there with some friends that have an almost identical setup to mine, but he has 35x12.50x20's (same Toyo RTs) on his truck and my truck didn't work any harder than his did. We compared numbers the whole way there and back. On the way back we ran I-10 across Texas in 100+ degree heat and the truck ran perfectly.

The truck has a Carli 2.5" leveling kit on it with 37's. It rubs on the radius arms at full lock and that is it.

 

That's a sharp looking truck. Love it.
The 37s look great on it, especially with the 20" rims.

Are those the toyo open country RTs? I've looked into those too, but wasn't sure I would like the looks on them.

I looked at Carli and their leveling kits are quite a bit more extensive than just adding larger blocks under the front springs. Is this the kit you have in yours?
Commuter System, Level 2.5" Super Duty Suspension system for Ford F250 / F350

 

They are Toyo RT's. I think they are good compromise of the MTs (what I had before these) and the AT2. I've been very pleased with them. I have the basic leveling kit. I wasn't too sure what I wanted when I bought it, but really liked the "upgradability" of the Carli stuff. I've been happy with it.

Here are a couple of pics of the tire tread to give you an idea of how they look.

 

Do you have the Bilstein shocks from the Carli kit in yours? How is the ride when compared to stock?

I really like the looks of your truck. So much I'm actually considering spending the additional money on the Carli kit.

 

My Bilsteins are better than stock, but it is not a night and day difference IMO. I have a buddy with the Fox (non reservoir) shocks that came with a ready lift kit and they aren't any better than my Bilsteins. I will say both are better than stock.

My main issue with the truck is the rear end shake on concrete highways. It drives me nuts. I have considered the Carli full length rear springs to fix it...just have a hard time pulling the trigger.

 

Put in my order for the Carli Backcountry 2.0 system yesterday. With full leave springs.

Now, to maintain my towing capability, I learned I need air bags.
If I can, I will put Carli's long travel air bags in. Any experiences with this?

Also, does anybody have a wireless air system in their truck? Any recommendations?

I'm thinking of adding the Air Lift 72000 Wireless kit:
Air Lift 72000 Remote Wireless Air Compressor System

Any input is appreciated.
Chris

 

FYI, With the Factory 20" wheel option the standard Tires are 34" tall.

 

So I learned the long travel air bags won't work with the 2.5" kit, they need at least a 4.5" kit.
Now figuring out an alternate setup.

And thanks to the input from the Forum I have 37" tires in my garage to go on the truck...

 

Stock leaf springs with a quality adjustable shock and then either one up off road OR precision metal fab traction bars with built in block to get the rake you want

 

Hey 89LX306,

I tried to PM you but your inbox is full.

I just got my Carli Backcountry 2.0 leveling kit with the full leaves in the rear put in and am now running stock king ranch rims with 37x13.50R20 Nitto Trail Grappler MTs on it. Mine does the same thing, rubs on the radius arms.

But it rides like a dream.

What did they do with the wire on top of the radius arm on your setup?

When I left the shop it was clipped in on both sides still but after I drove a few miles and pulled in to a parking lot I saw that it had pulled out of the clip and was dangling on the outside of the radius arm...exactly in the area where the tires rub on it. Did they relocate that on yours?

Chris

 

I didn't relocate mine. I have never had a problem with it. You can see in this picture that it has a little dog leg in the line right where the tire contacts and the actual clip is located a couple inches further back on the radius arm. That is how mine came from the factory.

 

As far as airbags go...

Have you thought about a standard air bag kit (firestone, air lift, etc.) with some Daystar air bag cradles. I have no experience with them, but figured I'd pass it along if you hadn't heard of them. Not sure if they would work for you or not.

I had firestone bags on my old truck also. It had a 4.5" lift. I was able to get a lift spacer from airbag to make up the difference for the airbags. With something like that it might work with the Daystar cradle. Just another option to research.

Daystar? - Driven by Design

 

I have 2011 SRW crew F350. I run Nitto Ridge grabblers 295/65r20 which are a little over 35" I tow a 5er that is prolly 16,000. I use Firestone airbags. The only issue I have had is the airbag system tends to leak, but that is most likely due to the cheap hose they send and the fact I have multiple connections. No issues with tires and towing. Minimum tire rub at lock/. Oh, and I have 2 1/2 level kit. LOVE LOVE these tires BTW.

 

Update for those following:

Ordered Carli's radius arms and a new set of caster correction shims. As soon as they arrive, they are going in. Hopefully then the truck will drive straight again.

While I wait for my parts, I'm tackling another issue: slight shimmy on takeoff. Does anyone else here have a 2-piece driveshaft? If so, did you shim your carrier bearing down when you lifted your truck 2" and if so how much?

Carli makes a bearing drop exactly for this kit that the shop that put the kit in charged me parts and labor for, but when I look at my carrier bearing, it hasn't been touched since it left the factory. So any starting point on how much I need to shim it down would be appreciated.