Supporting mods to run 37s offroad

I've done a bit of searching and see that most recommend swapping to 4.88 gearing to run 37s.

My question is, other than gears with cmc, some trimming, and suspension lift, are there other supporting mods necessary to run 37s without breaking stuff for moderate offroad?

 

@osidepunker @KevinK @papasmurf

 

Honesty the gears are not required but a nice to have ... a lift and some trimming and hit the dirt

 

I have instructions in our build thread. Look in the table of contents for 37s and body mount chop.

https://www.tundras.com/threads/komodo-my-wifes-daily-driver-and-high-speed-overland-rig.16989/

It depends very heavily on the offset of your wheels. Too much offset (like 0 or a negative number) makes it super hard to clear on a low lift like we have, 2/1 basically. Around +18 or so is really good.

 

you need to re gear your rear end to the correct gear ratio to correct your speedometer ,and also get your engine rpm/powerband to where it should be. it will make your transmission shift properly and also take some of the strain off your drive-line components. the right gear ratio depends on your engine/transmission combination. talk to a rear-end shop.

 

Thanks I will take a look

 

@KevinK I read through that... that's a lot of cutting. I'll keep that in mind and bookmarked for the future. We will see where I'm at on my 2.75 and 35s. I may be happy as a lark.

 

No, you don't.

And gears wont correct your speedo

I run 37s with stock gears. The Truck is a dog, but I also weight 8000 lbs. Gears would help bring a little power back and stop the trans from from hunting on the freeway, but they are not a necessity.

 

Yeah, it seems like a lot when you're reading through it, but it's not actually too bad once you get under there and start doing it. Body mount, pinch weld, front bumper if it's stock, skid plate if it's stock, delete sway bar if it interferes. It's just time consuming to measure, trim, measure, trim, rinse, repeat...

 

If you go gears with the 37's, a Speedo Calibrator is nice to have for dash gauges. Even with 4.88's and 37's, more mid range TQ would be nice. I have the BAMuffler 8" system, the truck does fine with normal driving and towing 4k lbs but more power would be nice.

 

Get a locker or lsd while you're at it.

 

If you re gear the rear end your engine and trans won’t have to work so hard. I changed from a 3:90 ratio to a 4:88 gear. Truck has a lot more power, trans shifts back like it should runs better

 

Yeah that’s especially noticeable on the 3.90.
The 07+ comes with either 4.10 or 4.30 from the factory so it’s less necessary to regear. We’ve been running 37s on the stock 4.30 for a couple years now and it’s not bad. Someday we’ll regear when add lockers.

 

So, 37s are out. My skinny 35s on my mild lift is where it's at. May reconsider 37s in the far future. The little amount I drive itd take 10 years to wear the tires out I have now