Will 37s fit on a leveled F250 (Offset/Lift/Trim)

The Ford F250 must be one of the coolest trucks ever built by Ford. It, therefore, comes as no surprise that it’s so popular and that so many owners fit bigger tires to these vehicles to enhance their appearance even more. Being such a big truck, 37” tires are becoming increasingly popular since they fill those arches so well and really enhance the aesthetics even more. So what are your wheel options when fitting 37s to your F250?

You can fit 37×12.5 on 20” wheels to a leveled Ford F250 with a 2.5 spacer kit. It is recommended to fit 2” caster shims to restore your caster angle back to the factory.  With a 0 offset rim, the tires will stick out past the fenders approximately 1 inch.

These offsets with zero rub are very popular with these 37×12.5s. There might be some minor plastic trim required, depending on which offset rim you opt for and how aggressive the tire tread pattern is.

Let’s now look at your fitment options in a bit more detail.

Will 37s fit on a leveled F250 – ALL YOU NEED TO KNOW

After spending many hours researching this topic to find out exactly which offset really works best with and without plastic trimming required, I found it so interesting how much these trucks vary. Some guys literally managed to fit a 2.5 ” ReadyLift kit with 37s on a stock truck and it sits as if it is running on 35s. No Scrub.

With that being said, another important question to ask is, does a 20×9 vs 20×10 wheel make a difference, or is it strictly the width of the tire that makes the issue? 

Let’s see which options are most popular

Option A

  • 2.5″ Readylift leveling kit
  • Track bar relocation bracket
  • Rims are Fuel in 20 X 9  
  • +20 offset rims
  • Toyo 37 X 12.5 X 20 tires

Option B

  • 2.5 Inch Readylift kit.
  • Rims are 20×10
  • -18 Offset
  • Tires are 37×12.5×20.
  • Minor scrub.

If you opt for a 20×10 rim then go for a more negative offset rim to keep scrub at a minimum. Of course, the opposite applies as well.  

Will 37s fit on a leveled F250 – Leveling Kit

When fitting a leveling kit to the front, some owners have reported the truck stance to be a little nose high. This can happen depending on the truck’s year model, so keep that in mind before going too high on the front. Some F250 owners actually prefer it a bit nose high, however. I’m not exactly sure why that stance is appealing.

When fitting a rear block, these vary in height according to vehicle year model.

When it comes to the rear, you want to fir a rear block to lift or level the rear out to improve the stance of the truck a bit. When fitting a rear block, these vary in height according to vehicle year model.

For example, the 2020 F250 uses a shorter rear block and many owners have success with a 2″ rear block compared to earlier models between the years 2017-19 that require a 3.25″ or even a 4”. That difference in block heights has no negative side effect when running 37s. 

Fitting 37s on Stock Rims

If you want to fit 37s while keeping the stock rims/wheel then you will be limited with tire options. Most owners reported that the only tire that fits nicely without any scrubbing is the Nitto Trail Grappler MT 37/ 11.5 r20. In this instance, the 11.5-inch slimmer width prevents any rubbing. Unfortunately, the tire options in this configuration are very limited.

This is one of the few options available if you are not prepared to move away from the stock wheels and want to prevent any rubbing. With even the stock wheels, in order to fit 37’s will require a minimum 2-inch leveling kit.

If you are running 18” stock rims your rear clearance and offset is limited so to rectify that a 1/4″ wheel spacer usually does the trick to push the wheels out a bit with 18X8 factory wheels.

Will you need Caster Shims when lifting your F250?

When lifting most trucks, especially those with IFS setups, you are altering the geometry of the suspension angles. Simply fitting a leveling kit affects the caster and front-end stability. It is therefore highly recommended to install 2° caster shims to restore the factory angles and prevent the so-called “death wobble” effect. It’s a worthwhile layout and inexpensive with many aftermarket options readily available.

The 2° shim specified with our 2.5″ lift systems not only restores the caster but increases it by 1° from the stock spec to ensure proper tracking with larger tires.

Which wheel offset works?

20×10 with a -18 offset combined with 37×12.50 AT tires requires a minimal amount of plastic trimming. The upside to this configuration is in most cases there shouldn’t be any rub on the UCA arms at full lock.

If you opt for wheels with less offset, in most cases there’s no need to trim anything for the 37s to fit. If you opt for anything more than -18 like say a -24 offset wheel, be prepared to do some minor trimming.

Will You Need to Trim Anything?

Cutting up your truck is never fun no matter how minimum they are. In some cases, however, again, depending on offset, tire choice, etc., you will be required to trim the area where your front mud flaps mount. Be prepared to take about an inch off.

There will be a slight rub occasionally when turning at full lock while backing uphill. To prevent this, as mentioned above, you need the correct offset and aftermarket radius arms to get no rub.

Will you lose power after fitting 37s

In my research, I’ve seen quite a few F250 owners complain that 37s are noticeably sluggish over a 35. Owners who tow and haul heavy loads report the power loss is minimal and nothing noticeable between before and after 37s.

Other owners, on the other hand, report that they did not feel the truck lost any power or acceleration when tested on the dyno.

Your heavy 37s being below the suspension fall part of the truck,s unladen weight, which means you should be prepared to lose 1-2 MPG in fuel economy. There’s no way of escaping that.               

WATCH – FITTING 37’s TO A LEVELED 2020 F250

Biggest Tires on an F250 – No Lift

Before you run off and slap on the biggest tires on your truck, you need to consider what your intended purpose is for the upgrade. Are you going off-road? Are you simply doing an aesthetic (looks) upgrade? Is the truck used for hauling, commuting, or towing? All these factors will play a part when considering a big tire upgrade. Your motive for the upgrade should be to determine what the biggest tire size you SHOULD fit for your application, rather than what the biggest size you can get away with. Bigger is not always better in all scenarios.

Your tire and wheel selection should be in-line with your application. A big tire upgrade with a smaller rim and taller sidewalls for off-road purposes will be very different from that of a bigger diameter rim upgrade with lower-profile tires, which is purely for aesthetics.

Your tire and wheel selection should be in-line with your application

As mentioned from the outset the largest you can fit without and scrubbing, or cutting of wheel arch plastic is the 34” on a 16” inch rim. (eg. 315/75/16) Most popular combinations of 34” can work.

If you are prepared to remove the mud flaps, you can go slightly wider with a 295 tire on an 18” profile.

Once you install a small 2” lift your tire and rim options immediately widen, so let’s see what your options are.

Biggest Tires on Stock 2017 F250 4×4

The biggest tire you can fit on a 2019 F250 with no suspension upgrade or aftermarket rims are: 275/65/20 or 295 on an 18”. If you are prepared to fit a 2” lift you can comfortably get away with a 37”x12.5” R20 wheel.

F250 User Experiences/Feedback

Let’s look at a few real-world examples of F250 owners that have fitted 37s and their experience.

F250 User Experiences/Feedback #1

I was ready to pull the trigger on the 2020 until I read about the height reduction and it has me concerned and wondering if I need to go with a 2019 instead. I currently run a 2018 with 2.5″ Readylift up front, rear is stock… on 295/65/20 Ridge Grapplers and OEM aluminum wheels.

I was wanting to run a 2020 with the same Readylift setup but go with 37×12.50R20 Ridge Grapplers on OEM Aluminum wheels, but am worried they might not fit like they would on the 2019 model (I know there will be rubbing on 2019 on radius arms). Has anyone done a 2.5″ Readylift on a 2020 with 37×12.50s yet? I haven’t seen any on what limited social media I can see through Google searches and haven’t seen anything but 35s on 2020s here. Picture examples would be excellent, particularly on stock OEM wheels.


I am not interested in going with anything other than a standard 2.5″ leveling kit. I trade in every 2 years, so anything past a leveling kits doesn’t make much financial sense. I also want to limit the amount of full blown modifications as possible.

Thanks in advance for any insight!

https://www.ford-trucks.com/forums/1616773-anybody-leveled-a-2020-and-done-37s-yet.html

F250 User Experiences/Feedback #2

 I just picked up a new F-250 Lariat offroad, crew cab with the snow plow prep, I installed a 2″ kit up front, stock rear blocks and am running 37″x 12.50’s with no problem at all plenty of clearance. Paul

https://www.ford-trucks.com/forums/1616773-anybody-leveled-a-2020-and-done-37s-yet.html

F250 User Experiences/Feedback #3

The ride is great! Very smooth and comfortable and the mud tires are way more quiet than what I thought they would be. The only thing that I’ve noticed is the revs of the rpm’s is low she lives around 1600-1800rpm’s. Its hard for me to reach 2000 rpm’s and when I do its not for very long as I have way exceeded the speed limit by then. I can notice just slightly a lag in early acceleration, but she still has the power to get up and go too. Another things is that its difficult to get out of 9th, not seeing 10th very often and when I do I’m exceeding 80mph. But as for gearing up and shifting I don’t notice it shifting they only time I notice it is when I and decelerating or breaking roughly around 50 to 30mps and then its has rough downshifting and what I think is high rpm revs to be in those lower speeds and not giving it gas. I can be around the 40s on the speedometer and its still in 7th gear. Now that being said I have not calibrated the speedo yet either and I want to say its a 3.31 gear ratio, I have to confirm that, so maybe I need to look into having the gear ratio changed as well. Still green with diesels and swapping out parts for aftermarket. Been doing a lot of reading on here and researching and learning how the whole forscan works so I can doing a bit of mods myself.

https://www.ford-trucks.com/forums/1616773-anybody-leveled-a-2020-and-done-37s-yet-2.html

Resources

https://www.ford-trucks.com/forums/1616773-anybody-leveled-a-2020-and-done-37s-yet.html

https://www.ford-trucks.com/forums/1616773-anybody-leveled-a-2020-and-done-37s-yet-2.html

Jade C.

4-Wheel drives and off-road driving techniques has been my passion for over 20 years. Here we strive to provide the most accurate, up-to-date, information about the functionality, common faults and latest technology built into most 4 Wheel Drives.

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