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rsr911
09-20-2006, 09:15 PM
Well since I don't want to high jack the H2 thread I figured I'd post here.

I've been more than tempted over the last 12 or so years to build an offroad 4x4 that I could license for the street, something fully fabbed like a crawler. In the other thread 1 ton axles where suggested. Since this would be a cheapy project would it make sense to find a wrecked 1 ton and start there? A V-8 was also recommended so I'm thinking wrecked small block injected Ford (sorry I'm a Ford guy), narrow the axles, build a frame/cage and hang the parts on it. If I build a removable plow bracket for it I'd have and easier time justifying it to the wife. :D

HWooldridge
09-20-2006, 09:24 PM
Over the past several years, there have been a great number of M35 "deuce and a half" trucks coming out of government surplus. You could very likely find one that was not running for less than $1000 (probably much less) and use the guts out of it. Axles are beasts as are transfer case and transmission. I might be wrong on my specs but I seem to remember ring and pinion are 5:38 to 1 or some such, maybe lower. I have seen at least one of these trucks with the rear axle removed and the bed shortened so it sort of looks like a Dodge M37 on steroids.

PS - I'm a Ford guy, too.

rsr911
09-20-2006, 10:00 PM
Now that's the kind of cheap and tough I'm thinking about! :D

Mental note to self: finish upgrading the CNC and get a CNC rotab for cutting splines. ;)

CCWKen
09-20-2006, 10:58 PM
If you're going to license it for the road, I'd start out with something that already has a title. It sure makes life easier in the long run. ;)

torker
09-21-2006, 12:12 AM
You can get TOO heavy pretty easy. Big ol' Rockwells etc are alright if you can live with a 6000 pound rig. The more weight you add the harder it is to fight gravity and mud.
You have to decide just what you want to do.
A mud buggy is a hell of a lot lighter than a rock buggy(that will survive in the real world).
My mud rail with a blown alky engine weighed 2200 pounds and was pretty easy on drive train compared to a rock buggy. The key to mud is massive wheel speed. Costs lotta money to spin them as fast as you need them to.
BTW...a lot of EB's had Dana 30 front ends. A D44 in an EB is very hard to find here.
There are rock machines that use some very light drive trains (Tiny comes to mind) but they would be limited when it came to packing gear etc.
A lot of rock guys use Chevy 4.3's also....check out Pirate...there's a ton of info on these engines.
I put one in the Yota I built and have a brand new one sitting in the garage to replace that one. I like them...pretty light compared to a V-8.
On the other hand...an EFI 5.0 is another of my favourites. Good power and great fuel injection.
Russ

BadDog
09-21-2006, 03:17 AM
Yes, like anything else, you need a plan to put together a consistent system. How many seat? How much gear? What range? What budget? What use? Will it need to handle multiple rolls and flops in a sustainable condition? All these questions and more need to be firmly nailed down

Then you figure out what pieces work for you. I would strongly suggest you loose the Ford bias as it may cost you money and performance in the long run. I have a general GM bias, all other things being equal, but I’ll run Ford, Dodge, or any other part that suits my needs. My rear case uses a Ford input shaft, bearing and retainer inside a GM passenger side drop case with a modified Ford 32 spline front output and a fxed yoke Ford rear output shaft. That’s mounted behind a GM 203 range box, and I use Dodge 1410 yokes housing Spicer life series u-joints. And so on...

If I were starting over, and wanted a good low budget general purpose rig for 2, I would probably look at a Formula X Chassis from Hendrix Motorsports. With that, and your choice of drive trains (Toy is the easiest, but you can run most anything including Ford EFI 302, which is not a bad choice). And older Toy SFA axles are actually amazingly strong, capable of running up to 37” tires with a few weak points addressed (like the Birfields. So, if I didn’t already have so much invested AND if I didn’t want 4 seats plus gear, I would go SFA Toy driveline with an X-Chassis and double triangulated 4 link rear with a asymmetric 3-link front. That’s a very decent crawler about as cheap and easily as your going to get into crawling.

If you insist on Ford, it’ll cost, but a 78 or 79 F250 4x4 comes with a High Pinion Dana 60 front, king pin knuckles, and a Dana 70 rear. Loose the body and build a truggy like mine and your nearly there, though you’ll want to loose the likely 400M under the hood.

If you want a truck/truggy setup, I always recommend starting with a 1 ton 4x4 and cutting down. Too many people try to start with a daily driver 1/2 ton (or lighter) and it’s always more money and WAY more work building up, than cutting down. My truggy pictured started with me bringing home an 85 Chevy K30 (M1008 for those that know). It belonged to a GM dealership tech who rebuilt everything (new seals, bearings, all wear items throughout) and then acting stupid rolled it. It had everything I wanted for less than lots of the K5 guys pay for a single Dana 60 front axle, and it was already rebuilt, rolling and ready to go on new tires.

You probably don’t want to narrow the axles, it’s a major PIA and you can no longer use off the shelf replacements. Even aftermarket alloys cost more. You also want width for off camber traversals and they will keep the rubber side down much more consistently.

And on Rockwells, they are heavy and old tech, often hard to find parts for, and the top loaders are hell to try and fit in a chassis. You really have to build around them. If you have the bank and really want to go all out on axles, look into Mogs for super clearance and longevity, though they have their own issues.

And this is just the tip of the ice burg. If you are really interested in this topic, visit www.offroadfabnet.com and do some reading, post your questions, and join the fun. :D There is also another site called Pirate4x4.com that used to be really good, and it still has lots of good tech, but it’s mostly populated by a bunch of smart mouthed punk wanna-bes now.

torker
09-21-2006, 08:36 AM
BadDog...very good advice!
The only thing you missed...you forgot to tell Christian how much time you invested in your rig. That's the killer IMO.
I was going to build an updated chassis for my mud rail after I sold it. I'm older and lazier now and just can't seem to find the 1000+ hours it takes to scratch build a chassis/glass body etc.
However...I see the odd machine kicking around that someone else has spent a fortune on and they are trying to sell it for a mere fraction of what they have into it.
Something to consider.
Russ

Evan
09-21-2006, 08:55 AM
If I build a removable plow bracket for it I'd have and easier time justifying it to the wife.

3 bottom or snow? :D If the former then you can get a farm tag for it. :D

BadDog
09-21-2006, 01:52 PM
Good point Torker. If you can find an abandoned project that fits your needs, that is ALWAYS the cheapest and fastest way to go. Like you I have been looking at my beat cage/chassis for some time thinking how much better I could do on a new one, but I'm too freaking old to start over. My son and I built that one together, and now he's completely lost interest, so there are sentimental reasons (as well as lack of help) for keeping what I have.

HWooldridge
09-21-2006, 02:13 PM
For you mud fanatics, I watched a pretty neat show a few days ago on Dish Network, channel 9476, RUSH. I think it's called "Mud Guts and Glory - Jungle 4wd" or something similar. Anyway, it was about a 4wd rally that is held in the jungles of Malaysia every year with about 30 teams starting and 20 or so finishing the 10 day event. As usual, the cameras followed only a few of the teams but you got to see most of the vehicles. Many were modern Jeeps or something similar but they had a Pinzgauer manned by a Dutch team and a vintage, stock WW2 MB - don't recall the nationality driving that one but it broke down on the trail and did not finish.

I have a Dodge M37 with PTO winch and believe one would have done quite well as winches were being used constantly and the little electric models were failing with some frequency. It was also noted that the Malaysian teams usually win and they use PTO winches. Obviously a very grueling event and anyone who even finished could consider themselves a winner. BTW, the Pinz finished in fairly good shape - the only major damage was a windshield smashed by a tree limb.

alcova
09-21-2006, 11:28 PM
One thing to remember about military ratings...2 1/2 ton rating is a cross country rating, for a highway use you can double it to a 5 tonner.

Walt

BadDog
09-22-2006, 02:56 AM
1/2 ton, 1 ton, 2-1/2 ton, the numbers really have no relevance to cargo capability in modern trucks other than as a rough classification moniker. And in my opinion, the military classification system seems strangely optimistic in that regard. Point of fact, the M1008 is nothing but a specially equipped Chevy K30, also known in civilian form as a “1 ton 4WD truck”. But even though cargo wise it has no upgrades from standard civi issue, the Military classifies it as a “1-1/4 ton truck”, and it’s certainly not capable of functioning as a 2-1/2 ton truck...

HWooldridge
09-22-2006, 02:22 PM
1/2 ton, 1 ton, 2-1/2 ton, the numbers really have no relevance to cargo capability in modern trucks other than as a rough classification moniker. And in my opinion, the military classification system seems strangely optimistic in that regard. Point of fact, the M1008 is nothing but a specially equipped Chevy K30, also known in civilian form as a “1 ton 4WD truck”. But even though cargo wise it has no upgrades from standard civi issue, the Military classifies it as a “1-1/4 ton truck”, and it’s certainly not capable of functioning as a 2-1/2 ton truck...

The military seems to have gotten away from cargo vehicles designed specifically for off-road tactical use during Vietnam, probably in an attempt at cost savings. It was easier to spec a Kaiser, Dodge or Chevy civilian truck and add the mil options than to design one from the ground up. The M35 and its variants are real beasts for off road hauling and can truly be called a "truck". They'll go almost anywhere if equipped with a PTO winch (and if you have sufficient cable anchors to get it out). IMHO, the only drawback is that they are a bit bigger than the average pickup and won't fit in a lot of civilized places.