Do I REALLY want 37's?

I am going to need new tires soon and I'm considering 37's. I am aware of the dirty sevens post with a lot of info in it, but I'd like to have a more pointed conversation about the realities of running 37's on a truck that WILL fully cycle suspension.

Current Setup: ADS suspension. Front is 2.5" RR C/O's. MCM UCA, and duro bumps. Back is Deaver 748's, 2.5" triple bypass, and hydro bumps. No BMC. Stock 18x8 steel wheels with spidertrax spacers (effectively a +25 offset, if my math is correct). 295/70r18 Cooper AT3 XLT's.

Proposed Setup: Suspension remains unchanged. Do a BMC, possibly fairly aggressive. Trim the stock bumper caps ("viper cut") or install an aftermarket bumper. Method 703 (17x8.5 +35 offset). BFG AT KO2 37x12.5r17.

Another problem I see is that I don't think I can fit a full sized spare 37" in the stock location. I have no problem trimming the tabs on the underside of the bed, but I don't think a 37 would fit between the rear shackles.

Here's the real question: Do you guys think this suspension/wheel/tire combo will be able to effectively cycle it's entire up travel and down travel without having to make major modifications to fender liners or other moving parts? I don't have any problems with a BMC or trimming the the bumper caps, but would prefer not to go further than that.

 

What about a re-gear?

 

First thing I would consider when going that large.

 

Yea, assume re gear to 5.29's.

 

KO2s 37"s are on the smaller side.More like 36"s. It's a good choice if you don't want to cut too much.
37's with 17"s wheels is great. will be a cushy ride.

 

Yes, part of the reason I was considering them. Also, they seem to be one of the only options available in C load. Tired of 10 ply E's.

 

also the KO3s about to come out so you might want to wait for them.

 

full spare is always a pb. 35" fits fine with cut tabs but I dont want to store a 37 in my bed. defeats the purpose. Main reason why I'm still on 35's

 

If they're available in a C load I might consider them. Might make deals on KO2's a bit better, too! $2500 for 5 new tires is a spicy meatball.

 

Hmm, yes this is a problem for me too. I fit my 295/70r18 spare under the bed without having to cut tabs but I don't see a way to get a 37 under there. I wouldn't mind a high clearance bumper with a tire mount, but dang those things are spendy.

 

These are good points, but back to my main question...Anyone with real experience on full cycling of the suspension with such a setup?

 

Probably need to page @reywcms @joonbug @snivilous @KevinK @831Tun or any of the other BASTRDs to get this question properly answered.

 

We just put 37's on our Jeep.

The answer is YES, you definitely want 37's.........maybe even 40's.

 

Just ask @KevinK I know he's got some real world experience with this. In the end, I'm guessing fiberglass fenders up front are necessary.

 

While I'm honored you'd think of me, I intentionally haven't commented since I know nothing about fitment on Tundras. I have 35s that don't rub with stock wheels and that's the extent of my knowledge but yes, when in doubt go big or go home

 

I feel @BiggHertz has a similar setup I believe on 37s

I can tell you there’s a few brackets on the rear bed area I cleaned up but I also still rub at full articulation but I’m also spring under with a custom bedcage and shocks going through the bed.

Up front at full bump for me in particular or anyone with long travel there’s a fair amount of cutting and massaging to get the full amount of travel. This includes front bracket by the headlight, upper inner fender well needs to be essentially fully removed. You’ll also want to relocate the secondary intake vacuum pumps as this rubs. But again this is different for me than yours but gives you an idea. I’ve also added a pic of what it really takes to have full travel. You can see the inner fender is essentially gone.

 

Was just about to tag him too. He's got the closest setup to what Mr. Hamster is looking for, 37s, modest lift, stock fenders and liners.

 

Yep my exact thoughts!

 

I enjoyed 37's on my Jeep JK, Pro Rock d44 axle, regeared to 5.13's, ARB lockers, bead lock wheels, red neck ram steering assist, bigger brakes, tires were Cooper SST Pro's 12.50 x 37 rode great on the road and in the rocks. Broke 4 drive shafts before I was finally able to put Tom Woods drive shafts in. Couldn't drive it for 2 years after I was rear ended in my Subaru while stopped to make a left. (Back injury) Sold the jeep. I'll dig up some pics and post them later. If your going to wheel it, go ahead and start a "repair fund." But if your just going to be cruising the mall you should be fine. Make sure your brakes are adequate. I promised the wife I wasn't going to mod the Tundra....(installed my 1st skid this weekend)

As far as your spare, I'd mount it in the bed. Nothing worse than having that junk hang off the back.
similar to https://www.palletforks.com/accesso...Z91OzHmbe3O4yLiO9VOE0xGP1UDJ4gZ4aAh0GEALw_wcB

 

Here's his writeup on getting them to "fit"
https://www.tundras.com/threads/bigghertz-white-shadow.101679/page-2#post-2614468

 

yes, I was thinking of him too. I read through his 37 journey on his build page, good stuff.

 

Also, one way to find out is going out flexing and field testing you’ll see what needs to be clearanced lol. Self clearancing is also an option lol


When in doubt cut it out

 

Ah, hadn't seen this one. He's got a nice truck, pretty similar to what I've built. Maybe he'll chime in. Thanks!

 

37’s are a game changer when you’re crawling. But they don’t help much if you’re still limited by your stock bumpers and rear hitch. Best advice I can give is swap out the front bumper first. Not only will it drastically improve all your angles, it’ll make fitting those 37’s so much easier.

 

Good point about the brakes. 37s necessitate a brake upgrade. EBC yellow pads are the most common solution.

 

Yes. Clearancing should be done after self clearancing.

 

It seems I have been summoned...

Mid-travel specific opinions below:

With regards to most of clearance challenges up front, a lot of variables are at play eg (wheel offset, track width due to alignment figures, alignment values themselves specifically caster, dynamic alignment changes-suspension mounting point compliance (spherical/ball type joints vs rubber/PU bushing)).
Overall diameter of the wheel assembly also plays a huge factor especially at full bump, where the top of the wheel WILL contact the inner fender well even with the plastic liner removed. you're options are to tub the front end or limit up travel by shimming down the bump stops about 1/4 to 3/8 inch (YMMV)

You can fit 37s without "viper mod" and retain all of your liners in place. occasionally you'll need to replace the plastic clips when you go deep into the up-travel or replace with jack nuts, stainless washers and screws.

Passenger side example below (ignore the arizona mud).







Rears do present some challenges much easier to mitigate, wheel offsets to prevent contact between wheel and fender at full bump, trim some plastic from the bolt head covers.

As with the front, you will hit some sheet metal (where the fender arch to bedside support bracket bolts up to) and you'll occasionally need to replace the plastic clips or replace with jack nuts, stainless washers and screws.

I've left my rear fender liners in and you can see they do become abraded by the wheels at really really heavy bump. but more often than not they're fine.








37s are a great choice, but you will most certainly have to commit to getting the most of them and the suspension system...

/rant

-JS

 

"don't hit the trails without it" - some ya-hoo

 

I ask this same question to myself on an hourly basis.

 

Really good info, thanks for your input. As with most choices in life I'm just trying to figure out if the juice is worth the squeeze. Between the brakes, re-gear, trimming, spare relocation, increased wear and tear on the drivetrain, etc. I'm still undecided but the info here from guys who have been there and done that, is really valuable to me.