What supporting mods to run 40s

[maxamillion2345]

40s on stock axles are awesome (for clearance) if you can keep them together. I agree with the RCVs, ARPs, truss what you can, hydro assist and beefier steering links/joints, lower tcase gears, chromos and bigger dowels in the rear, and collect spares.

 

[joez]

Howd you go through the body and seal it up? Sandwich with plates?

Ive been wanting to do a hybrid on mine for a while. Maybe some day Ill get around to it.

No, I was afraid of the metal fatiguing and causing tears down the road if I fully welded it. Holes are exactly 1.75", so the tube fits snug, and I ran them through the main bracing on the outside edges of the roof. That part is welded, and the opposite side of the tube is welded to the sheetmetal on the inside. This way it can still flex slightly. Inside of the roof is packed with black RTV, and the outside is actually sealed with neoprene based flashing cement.

There is almost zero leaks from the cage. I have one on the driver side. I left the truck out in the rain on a day when we got 6" of rain in 4 hours, and it had a couple beads of water rolling down the tube when it was over.

 

[Kevin8086]

What is this Extra doweling y’all are referring to? And what should be upgraded to ARP hardware?

 

[maxamillion2345]

What is this Extra doweling y’all are referring to? And what should be upgraded to ARP hardware?

Rear Axle Hub Stud and Dowel Pin Upgrade

Theres a lot of threads regarding this but basically any of your hub studs and steer arm studs etc... you'll probably end up wanting hellfires anyway Id think

This is a long costly road fyi

 

[Kevin8086]

Such a costly road. So crazy

 

[Kevin8086]

Rear Axle Hub Stud and Dowel Pin Upgrade

Theres a lot of threads regarding this but basically any of your hub studs and steer arm studs etc... you'll probably end up wanting hellfires anyway Id think

This is a long costly road fyi

So ur saying don’t go 40s. Lol

 

[maxamillion2345]

I'm not saying that. I mean honestly I want to step it up to 42s... but uhh 40s on stock axles are bitching for clearance if you can keep s*** together but its not easy or cheap. I don't think theres a right or easy answer on if its worth it or not. Or if at some point you'll get tired of stock axles and 40s and try to go tons, which is also a long expensive road. Guys are all over the place I think. It's a personal decision, keep researching.

 

[Kevin8086]

I'm not saying that. I mean honestly I want to step it up to 42s... but uhh 40s on stock axles are bitching for clearance if you can keep s*** together but its not easy or cheap. I don't think theres a right or easy answer on if its worth it or not. Or if at some point you'll get tired of stock axles and 40s and try to go tons, which is also a long expensive road. Guys are all over the place I think. It's a personal decision, keep researching.

I’m tryinb to make the truck as aggressive as possible but still be able to drive 15 hours to Colorado and wheel and drive home. If I can’t run 40s on chromolly axles and stock housings with HD tie rods for steering and maybe a hydro assist reliably then it sounds like 40s may be the tipping point of cost/benefit factor. My 37s have been very good to me and seems like a good balance but of course I want more. I feel like 37s are no problem for this Truck to handle and was hoping 40s would be within the spectrum but the last thing I want it is to break something every time I go wheeling and I go a LOT. I’m not really wanting to spend any more money past the basic upgrades of axles and steering and ARP studs/bolts. I’d rather spend my time wheeling vs working on the truck

 

[maxamillion2345]

37s are probably a good progression point too. If you can build it up to run 37s then maybe at some point you make the jump to 40s. Or maybe not.

Or just commit and go for it?

I think most guys with 40s probably got there gradually though?

Edit: hmm disregard, didn't realize you were already on 37s.

I guess buy a set of 40s and make s*** happen. You can make Yota axles live on 40s but use good judgement and upgrade what you can. Also, weight is a huge consideration. I know guys with mini trucks who run or ran 40s on yota 8" axles wheeling really hard but theyre so much lighter. The weight of the 80 series takes its toll.

Obviously theres a number of 80s on 40s with stock axles, so it can definitely work but a lot of this game is trial and error, even following in others footsteps isn't 100%

Idk if I'm making any sense and others may or may not agree but thats just my thoughts.

 

[NateMob]

@ExpoMax can you help this man out with his dilemma? You wheel 40s a ton but are smart about using lockers and the skinny pedal. I know we discussed you stepping down to 37s once for various reasons.

 

[Kevin8086]

37s are probably a good progression point too. If you can build it up to run 37s then maybe at some point you make the jump to 40s. Or maybe not.

Or just commit and go for it?

I think most guys with 40s probably got there gradually though?

Edit: hmm disregard, didn't realize you were already on 37s.

I guess buy a set of 40s and make s*** happen. You can make Yota axles live on 40s but use good judgement and upgrade what you can. Also, weight is a huge consideration. I know guys with mini trucks who run or ran 40s on yota 8" axles wheeling really hard but theyre so much lighter. The weight of the 80 series takes its toll.

Obviously theres a number of 80s on 40s with stock axles, so it can definitely work but a lot of this game is trial and error, even following in others footsteps isn't 100%

Idk if I'm making any sense and others may or may not agree but thats just my thoughts.

Hahahah, ya I’m not a progression kind of person. Last think I want is to cut up the truck for 40s and it ruin the truck and I can’t go back to 37s because it would look silly and be silly to do all that and be back at 37s with a cut up Truck. I like the go for it idea. Wife, not so much

 

[Kevin8086]

@ExpoMax can you help this man out with his dilemma? You wheel 40s a ton but are smart about using lockers and the skinny pedal. I know we discussed you stepping down to 37s once for various reasons.

Yes please. Why did you even think about going back to 37s? I can’t see that being an option after cutting the Truck

 

[ExpoMax]

Yes please. Why did you even think about going back to 37s? I can’t see that being an option after cutting the Truck

Haha there is a reason I haven’t commented in this thread yet. To many big egos to tell everyone how to build their own truck. So many think it’s so outa this world to wheel a truck with 40s and have it be reliable on stock housings.

A bit of background though. My truck was build to overland and do hard trails. I am not willing to give either up. That's why I am not 3-linking it or d60 crap for the very reason I could not drive 85 going down to Moab without feeling like I'm going to die. This is also my daily driver and I plan to be living out of my truck in a year or two traveling the US/Canada

Yes I wheel on my 40s all the time. Just hit 9k miles with the tires, 3 Moab trips etc etc etc and I have complete trust is my setup.
It’s been pushed hard and hasnt let me down yet.

For the question about going back to 37s. Yes I thought about it for several reasons. Am I going to? Very unlikely.

About the cutting for 40s then going back to 37s....well even if I had 37s I would have cut just a much to get the most up travel I could. Look @jcardona1 truck. He cut at least as much as I did and his truck looks awesome with 37s.

A couple reasons I though about going to 37s is:

I plan to drive my truck to Alaska in the near future. Plan is about 10k mile road trip. I can get 37s in an a/t. Most likely gain about another 1/2mpg too. If they ever have 40s in a ko2 or something, that would be my dream tire. Lighter weight, better mpg, better at 80mph etc.

Accelerating and braking are better with lighter wheel/tire combos. 37s would brake better.

Thinking about wheeling with the 37s, I could definitely push it a little harder. Heck iv thrown around the idea of chucking some 35s on so I can be throttle central, but why do that when I can crawl so much with 40s? Personally wheeling with so many rigs on 35s, I definitely have to use a lot less skinny pedal.


With all that said, I could of never imagined when I built this truck 6 months ago how much fun I’d have with the 40s. At this point 40s were probably my best life choice to date haha. The amount of people that I have met, the minds you get to blow every single day, it’s just a really cool thing. Plus all the crazy absticles you get talked into doing cuz you got the biggest tires lol! 35s are normal, heck even 37s are getting there, life is to short to be normal. Go for the 40s, it will be a great adventure at least.

I had all kinds of people thinking I was crazy that I wanted 40s. I was told "it wont drive well" or "wont be reliable" or "you'll always be throwing money at it". Proved them all wrong. Do the 40s, if you going to break in a spot with the 40s, most likely would of broken with 37s too. If you don't drive like an idiot or how I imagine @nukegoat does, you'll be fine.

 

[ExpoMax]

37s are probably a good progression point too. If you can build it up to run 37s then maybe at some point you make the jump to 40s. Or maybe not.

Or just commit and go for it?

I think most guys with 40s probably got there gradually though?

Edit: hmm disregard, didn't realize you were already on 37s.

I guess buy a set of 40s and make s*** happen. You can make Yota axles live on 40s but use good judgement and upgrade what you can. Also, weight is a huge consideration. I know guys with mini trucks who run or ran 40s on yota 8" axles wheeling really hard but theyre so much lighter. The weight of the 80 series takes its toll.

Obviously theres a number of 80s on 40s with stock axles, so it can definitely work but a lot of this game is trial and error, even following in others footsteps isn't 100%

Idk if I'm making any sense and others may or may not agree but thats just my thoughts.

I went straight to 40s! Best decision ever haha

 

[Qball]

As soon as you go 40 then you will want 42, just a little bit more! Is the 40 to wheel or to show?

Here is a good starting point if you really to wheel with 42s:

Trailer with towing rig
Welded tube chassis
6.2, 6 speed tranny and dual case
Custom 3 link front and cantilever rear suspension
King’s coilovers and quad bypass
Dana 60 front and 80 rear
Seats
Helmet
Gas pedal

 

[Kevin8086]

As soon as you go 40 then you will want 42, just a little bit more! Is the 40 to wheel or to show?

Here is a good starting point if you really to wheel with 42s:

Trailer with towing rig
Welded tube chassis
6.2, 6 speed tranny and dual case
Custom 3 link front and cantilever rear suspension
King’s coilovers and quad bypass
Dana 60 front and 80 rear
Seats
Helmet
Gas pedal

Definitely don’t want to have to trailer the rig. At all

 

[maxamillion2345]

Definitely don’t want to have to trailer the rig. At all

Sure seems like hes talking about building a tube buggy.

I don't think trailering is a must to run 40s. I've run my nittos down the hwy, unbalanced, for hours at a time at 75mph. A stockish suspension setup you'll be fine. Biggest thing will be gearing/power imo.

 

[Qball]

Sure seems like hes talking about building a tube buggy.

I don't think trailering is a must to run 40s. I've run my nittos down the hwy, unbalanced, for hours at a time at 75mph. A stockish suspension setup you'll be fine. Biggest thing will be gearing/power imo.

Buggy is about the only way to wheel 42s hard.

 

[White Stripe]

One thing that can be done for a stronger front axle is take a fj60 front housing, cut off the knuckle balls, install 4plus products housing spacers on both sides(this will make it fj80 width, then install fj80 knuckles. Then source a 100 series or tundra 9.5 diff with the bigger shaft pinion that accepts 32 spline axles. Nitro makes 32 spline front axle shafts and birfields. For the housing itself, a simple gusset all the way across the front from knuckle ball to knuckle ball will keep it from bending but need a 3link for the room for a gusset. I think the birf/axle kit if still offered is around 1100.00$ if I recall. Going from 30 spline to 32 spline according to the axle shaft chart I have is a 25% increase in strength.
For the rear you could use the same 100 series or tundra 9.5 diff with a arb locker. The locker can be modified to run 35 spline shafts. Going from 30 to 35 spline shafts according to my chart is about 60% greater strength. Have I done any of this? No. Just stuff I picked up from reading pirate4x4 yota build threads to see how far a 9.5" axle can be taken.