37"s

[atvspeed4]

6.2L nice choice for a LSX type motor! Are you getting one out of an escalade or crate motor. Im sure they will but make sure they remove the VVT.

 

[Ron46]

My goal is when I am out of college and get my mechanical engineering degree, I want to drop a cummins 4bt into the h3. It will definitively fit, just beefing up the front end is my concern. I have a fully rebuilt 5.9 cummins right now sitting on the shop floor, but that wont fit without some cutting

 

[4speedfunk]

Nice -- what's next?

Well...after a couple wheeling trips and lots of street driving, I have decided to make a few changes. I knew this would happen and its just part of the "fine tuning" that comes with a project like this.

First & foremost is my turning radius. I got very spoiled by the stock R&P steering, and that is one of the great things about the H3. I knew the solid axle would probably be less but, I want to try to get as close as I can to the stock feel. Right now my turning is limited by the lower links. Both the 35"s and the 37"s rub the link bars, so I'm looking at several ways to fix this problem. Dana 44's come with adjustable stops on the knuckles, and I have them set to prevent tire rub...but the trade-off is that I cannot turn as sharp as I would like to. So I plan to re-locate the rear mounts for the lower links, further inboard. Presently, I have the mounts welded to the bottom of the frame rails, and I want to build a "shelf" on the inside of each frame rail to allow me to move them approximately 2" further inboard. This should open-up some valuable real estate for tire clearance, and I can then re-adjust the stops on the knuckles to allow tighter turning. The other option is to use a "bent" link bar but, I'm not crazy about that for several reasons. I would like to hear from Recon on this topic. His lower mounts are welded in exactly the same location and I wonder if he has similar issues in regards to turning radius.

Second mod planned is to make my own pitman arm. This has more to do with "feel" than actual function. I basically want to speed-up my steering, to keep my elbows from flying around when wheeling in and out of tight trails. A slightly longer pitman should quicken my steering to feel more like a stock H3, and less like a farm tractor. Plus, with the additional clearance at the tires...its very possible that I might run out of "swing" with the stock 5.25" long Nissan pitman arm, before I reach full-lock. I think a 6.00" arm should do the trick. Unlike Saginaw steering boxes...the Nissan unit has very few choices, and almost zero aftermarket support for pitman arms. So, today I'm drawing my new pitman arm up on CAD and getting it cut from 1" steel plate. I plan to cut up the stock arm and weld the Nissan-splined hole to the new arm. The other end just requires a tapered hole for the 1-ton DLE (and I already have the reamer).

In the scheme of things...these tweeks are very minor. The truck actually drives great as-is but, I'm very picky. If I was a Jeep guy, I'de probably wouldn't mess with trying to get it better.

:giggle: -Har.

 

[ReconH3]

I don't mind having less steering. Mainly because that's what causes most failures on the trail. The more you turn the wheel when there is stress, the weaker it gets.

Bent anything is never good because it's much more prone to bend out of whack when under stress. A straight bar takes much more force to bend, then one that is already bent.

 

[4speedfunk]

Yeah...I completely agree with you, especially when stomping the gas with the wheels cranked. I'm always throttle shy when turning tightly...that comes from years of wheeling with IFS CV shafts! Still...I did quite a few 3-point turns last month (at Redbird ORP), when I should've been able to make corners in a single pass. I've driven other SA D44 equipped rigs and as long as the tires don't rub...they can safely turn much tighter than where I'm sitting at now. I'm talking more about general navigation in tight areas, and not really "under throttle".

Bending the links has several problems. Obviously the strength issue you speak of....but I'm also thinking they might droop (with the bend toward the bottom). This is because I'm using Johnny Joints on both ends, and they have some inherent twist-ability built into them. If I did go for the bent links, I would want a fixed urethane bushing on one end to keep the bend facing the direction I need. Also with the JJ's I'm double-threaded which makes link adjustment a piece-o-cake. With a bend in the middle, it would be difficult to rotate the link in place to adjust it. Lastly...I don't know of anybody around here that can properly bend .250" wall 2" DOM. That's much thicker than the typical roll cage material my tube guy is used to. So for all these reasons...I think moving the links inboard is a better idea. I think 1" to 2" is all it would require to gain 10 to 15 degrees of steerage.

One downside to using the GM axle is the big leaf-spring perch that is cast into the pumpkin on the passenger-side. This casting basically limits how far inboard you can weld the link mount to the axle tube. Your Dyna axle probably has alot more tube to work with...nice stuff. I've got mine tucked in as far as they will go (on the axle end)...so any more clearance will have to be done at the other end (on the frame). The nice thing about the Johnny Joints, however, is that they have 10-15 degrees of fluff to work with...so they should align themselves to the new mount locations without any grief (hopefully).

 

[Portager]

So this may sound rather retarded as I'm not much mechanically inclined. I blame a few things for this but we won't go into that.

Anyways at the end of this month I am having a 6.2L V8 engine swap done from Mash Motors, and after reading through this whole thread again I feel confident in assuming that with the extra power I will have to compensate for larger tires, would a 4.56 CI Diff w/ Locker up front be an okay match to run 37's?!? Maybe I'm an idiot for asking this but I figured I'd ask this and just let the chips fall where they may about this!

If your wondering the swap is going into a 2006 H3 that's also getting a 4:1 swap into it as well.

I was waiting for someone else to answer this question because I don't want to be the negative guy (at least not all the time), but since nobody has responded yet, here is my opinion for what it is worth.

It takes a large team of engineers to design and build a reliable vehicle. In my 55 years of experience I have seen very few after market modifications that improved reliability relative to the factory setup.

If you're going to swap a 6.2L for a 3.5L you're going to need to upgrade the entire drive train. You'll have too much power and torque for the transmission, transfer case, differentials, half shafts, maybe even drive shafts so plan on upgrading them all from the start or you'll just have to tow it home and replace them one at a time. You're also going to be increasing the weight on the front end so you might want to get torsion bars out of an H3 Alpha.

In my personal opinion, you would be much better off to get a low mileage H2 with a 6.2L. You'll probably spend less money buying a good used H2 with a 6.2L and you'll have a more reliable vehicle. Plus you'll still have a reliable H3.

 

[SC_Hummer_Guy]

I was waiting for someone else to answer this question because I don't want to be the negative guy (at least not all the time), but since nobody has responded yet, here is my opinion for what it is worth.

It takes a large team of engineers to design and build a reliable vehicle. In my 55 years of experience I have seen very few after market modifications that improved reliability relative to the factory setup.

If you're going to swap a 6.2L for a 3.5L you're going to need to upgrade the entire drive train. You'll have too much power and torque for the transmission, transfer case, differentials, half shafts, maybe even drive shafts so plan on upgrading them all from the start or you'll just have to tow it home and replace them one at a time. You're also going to be increasing the weight on the front end so you might want to get torsion bars out of an H3 Alpha.

In my personal opinion, you would be much better off to get a low mileage H2 with a 6.2L. You'll probably spend less money buying a good used H2 with a 6.2L and you'll have a more reliable vehicle. Plus you'll still have a reliable H3.

Have already taken most of what you stated into consideration numerous times, and they are all being upgraded at the same time. Trust me I'm not doing this half-assed only to be disappointed later. I have had many talks with the owner of Mash Motors who has a 10' H3T that he did the 6.2L swap in an runs 37" Toyos and has been running and wheeling that set up for awhile. This won't be within the first 10 swaps into a Hummer that he has done either. Granted most of the swaps he does are into H2's but if the owner has swapped his own H3 and run it for a good bit, and I'm actually investing to have it done right the first time with upgrading the front end (minus the rack of course but that's another story) then I feel confident in my choice!

Mostly the reason I'm doing all this to my H3 and not buying an H2 is that I want to do something different than the norm with my truck, and I have a certain love attachment to my truck that will cause me to never sell it, I swear I will drive it till it blows up with me in it! I don't really care what I have to do to make it work with the new engine, many here have gone into new areas of fab and engine stuff with their trucks and most asked WTF are you thinking? Or were really excited for the outcome. Yes I don't have the expertise that most have here with fab or mechanics, but I blame that from growing up without my dad to teach me, or the money to put myself through auto classes where I could learn. But I have the money now to have others who do have that knowledge and have done it already before to do it for me! And NO ONE better take that as me throwing I have money around cuz it's not. I just have been blessed with a loving gf, and a great job that I can afford to do this. If I had time to learn I would, but I have Med School to worry about soon, so auto classes will have to wait a bit! Lol

I can appreciate what you have stated and I do take it into consideration, but the certain love I have with my truck just makes me wanna build it now, wheel it now, and build my own custom truck later when I know how!

Besides with 25 credit hours a semester, not like I have the time even if I knew how haha!

Check out the Mod List Thread I posted here and you will see I have covered most everything you listed. But I def appreciated the feedback, it's why I posted in the first place!

http://www.hummer4x4offroad.com/for...our-Thoughts-!&highlight=hummer+shopping+list

Cheers,
Cody

 

[atvspeed4]

Honestly I think that is very respectable. I have always wanted to put a 6.2L in my h3. A few years ago I remember a guy posting up on a forum pictures of his 2006 that he put a 6.2L into I think it was yellow if I remember correctly. Its really not that far fetched. cast iron front diff and for CVs install the RCV outer cv joints. As for driveshafts, stock rear will be fine, the front shaft has a CV transfercase side which might give you a problem but can be replaced with a upgraded D shaft.

 

[06 H3]

cody, where did that guy go? The dude on 37s with the 6.2...I wanna talk with him lol Not to do the same project but just to see what his setup is like and the type of wheeling he does. I think it would be cool to have him document a build thread on here.

 

[SC_Hummer_Guy]

When I ship my truck to him imma convince him to get on here and create a build thread. i asked him about his truck and talked about what he does. Said he used to be on the old forum (not sure of his Tag), but since the split has been so busy with work that he rarely has time to get on forums and just play around and post. Heck right now he has 2 H2's in the shop getting swaps, one of which is a 1000HP engine into an H2 (why i have no idea). And then when they leave is when mine can finally get shipped out to go into the shop. he has no room there now to even store it haha! but i will see what i can squeeze outta him when I fly to Kansas once my truck makes it there, and take some photos if he lets me!

 

[rsc]

Okay, I know that the 315's (34.4") fit with no mods necessary and the 37's (345/75R16 is 36.4") need a 1" body lift minimum to fit. My question is WHY don't the 37's fit, is it the height or the overall width that scrubs? In particular, would a 325/80R16 that is only ½" wider than a 35 but still 36.4" tall fit on the front? I'm at 24.6" on the t-bar crank and have 3.5" over shackles in the back and wonder if the 1" body lift is a must on the narrower 37.

 

[58Bisc]

I'm at 24.6" on the t-bar crank and have 3.5" over shackles in the back and wonder if the 1" body lift is a must on the narrower 37.

I'm sure you have heard this before, but it has been proven time and again that anything over 23 1/2 will tear up your front end. It throws the angles off. 37's will just break it faster with the added weight. Backed down to 23 1/2, one inch body lift and trimming seems to be working on the H3 that run this set up. 37's rub the H3 (not H3T's) in the rear on the rocker panels at full flex. Saws all is required. Up front it is the sway bar and the inner fenders hit. I would think (no facts to back this up) that your 325/80/16 plan would work with the sway bar, just by not turning to full lock, but the cutting, even with the body lift will still be required.

Forgot to mention that on the v8, 37's are no issues with power. On the L5, gearing is required, but not available on the stock front differential.

 

[rsc]

Sorry 'bout that, I meant 23.6" on the front. The body lift is easy enough, just trying to get a good idea of what's gonna work.

 

[58Bisc]

Engine size or gearing seems to be the key. Trimming really is not an issue and can be done cleanly if that is required. H3T's have larger rear wheel openings then the H3 and don't require the trimming out back. Many question the weight of the 37's as a factor, but people are running some heavy 35's (including me) out there and the front ends seem to be holding up. Of course wheeling is also a factor. How much and how wheeling is handled play big factors in front end durability. IMHO, know one really knows for sure how long the H3 will stand up to the 35's, let alone the 37's. There has to be a first for everything, you could always try and let us know.

 

[I 8 A Jeep]

It’s happening hurricane 37x12.50x20 rockstars with a 3 inch bilstein 5100 wulf kit I will post next week

 

[I 8 A Jeep]

Getting put on next week