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Secret sauce? 37s on factory suspension (kinda) and factory 20s. No rub.

TD_Wubs

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Backstory - needed new tires for ‘21 Hemi NE. Settled on 35x12.5 (or 295/65) on factory NE 20s. On Black Friday fired up Discount Tire website to buy the new(ish) Falken Wildpeak R/T. 50k tread warranty, 10-ply, E load. Decided to research the tire just a little further on the Falken website. Found that they offer a 37x11.50, that weighs less than the 35x12.5 and only 5 lbs more than the 295/65. Anecodotal evidence (ie, limited forum postings) indicated that the 37x11.5 could fit with little to no rubbing. Pulled the trigger on the 37x11.50s. They ended up costing slightly less than either the 35x12.50 or 295/65 tires, so kinda a no brainer.

Suspension lift was not in the budget but i moved on the Thuren sway bar. Installed last weekend. Took the factory wheels/tires to Discount Tire this morning and they swapped on the new tires - they wouldn't install the 37s on a factory suspension truck.

Great news - the fit is flawless. No rubbing whatsoever. Sway bar provides clearance in the front. No rubbing on wheel well liner or radius arms. No noticeable loss in power or acceleration. The sway bar plus the increase in sidewall has led to a better ride. I'm so incredibly stoked that the new rubber looks so good and fit so well.

I'll post again with an update after living with them for a while.

Side shot 2.jpgRadius arm clearance 2.jpgSway bar clearance 2.jpgWheel well clearance 2.jpg
 
These trucks look great with 37s. I'm running toyo at3ws. Even with the 3.73 gears, the truck is great. Mine is lifted so anything smaller would look ridiculous.
 
Backstory - needed new tires for ‘21 Hemi NE. Settled on 35x12.5 (or 295/65) on factory NE 20s. On Black Friday fired up Discount Tire website to buy the new(ish) Falken Wildpeak R/T. 50k tread warranty, 10-ply, E load. Decided to research the tire just a little further on the Falken website. Found that they offer a 37x11.50, that weighs less than the 35x12.5 and only 5 lbs more than the 295/65. Anecodotal evidence (ie, limited forum postings) indicated that the 37x11.5 could fit with little to no rubbing. Pulled the trigger on the 37x11.50s. They ended up costing slightly less than either the 35x12.50 or 295/65 tires, so kinda a no brainer.

Suspension lift was not in the budget but i moved on the Thuren sway bar. Installed last weekend. Took the factory wheels/tires to Discount Tire this morning and they swapped on the new tires - they wouldn't install the 37s on a factory suspension truck.

Great news - the fit is flawless. No rubbing whatsoever. Sway bar provides clearance in the front. No rubbing on wheel well liner or radius arms. No noticeable loss in power or acceleration. The sway bar plus the increase in sidewall has led to a better ride. I'm so incredibly stoked that the new rubber looks so good and fit so well.

I'll post again with an update after living with them for a while.

View attachment 66175View attachment 66174View attachment 66176View attachment 66177

Odd.

Do the NE wheels have different backspacing than the chromies?

My 2020 with 285/65R20 Falken A/T3W's rubs the paint on the radius arms. Also makes me wonder if the R/T tread section width is actually narrower.
 
They (the more common 12.5x37) usually rub the radius arm, not the sway bar on stock wheels. Given you are an inch narrower that probably gave you just enough clearance.
 
that last pic looks like it'll rub under flex but could be my eyes. Glad it worked for you, I've been struggling with the choice in size.
 
that last pic looks like it'll rub under flex but could be my eyes. Glad it worked for you, I've been struggling with the choice in size.
It may rub when flexed, but i don't have a lot of opportunities to flex these days. If it rubs, heat gun to the liner for a little massage should help. And I struggled on tire size, but the cheaper price of the 37s vs the 35s made the decision for me.
 
Odd.

Do the NE wheels have different backspacing than the chromies?

My 2020 with 285/65R20 Falken A/T3W's rubs the paint on the radius arms. Also makes me wonder if the R/T tread section width is actually narrower.
Not sure about backspacing of NE wheels, but it could be the R/T tread with. Falken's published info says these 37x11.50 are 11.7" wide wereas your 285/65s are 11.4" wide.
 
Not sure about backspacing of NE wheels, but it could be the R/T tread with. Falken's published info says these 37x11.50 are 11.7" wide wereas your 285/65s are 11.4" wide.

That's listed overall width. Though still odd that it looks to have more clearance at the radius arm.

Now wonder if the LB or 3500 has more steer angle to offset the wheelbase... That said, I know some have cut/ground their stops down to get a little more (not me).
 
May be helpful to post the actual size of the tires and what psi you measured at. It’s not uncommon for a 37” to measure closer to 35.5” especially when it’s rated for 65 psi and you’re running 40

Width can make or break your fitment, you definitely fit as much tire as you could. It’s odd that you don’t rub the radius arm but I’m happy for you.

Also, you actually have more clearance turning the wheel on stock height than you do with a small lift if you don’t change the radius arm. As you lift the truck, the axle moves out of the center of the arch and toward the rear of the arch which is where the fender clearance issues occur.

Your post makes me happy that I didn’t go to 37s last week when I got new tires and stayed on 285/75-18 which is a taller 35 and 11.50 wide. Not that yours looks bad but it’s not the setup for me. I have 1” front lift.
 
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That's listed overall width. Though still odd that it looks to have more clearance at the radius arm.

Now wonder if the LB or 3500 has more steer angle to offset the wheelbase... That said, I know some have cut/ground their stops down to get a little more (not me).
You can see from my swaybar clearance pic above the tread contact patch indicates it’s definitely narrower than the tire. Lessens potential contact.
 
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You can see from my swaybar clearance pic above the tread contact patch indicates it’s definitely narrower than the tire. Lessens potential contact.

Tread is always narrower than the tire sidewall or section width. Tire size is based on section width, not tread width, not sidewall width. That was my point. If the tread width is the same or slightly less on the 37x11.5 than the 35x11.5 (my 285/65R20 are actually double marked as 35x11.5).

Anyway, glad they fit for you, I'd not consider 37 anyway with the load I'm pulling, +1 size is enough for me.
 
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