Hello!


i have seen some vids and info an H1 which got an upgraded suspension system from either Meritor or Oshkosh, which improved their GVW to 18.000lbs.

Now as far as i know the H1 was designed back in the day for a GVW of around 10.000. I do not know what they did to the frame to increase it to 12.000 but maybe there was nothing to do anyways because the frame could always handle those 2000 extra.

But its a long way from 12.000 to 18.000 so i like to know what they changed or if its is a completely new frame anyways???

Greetings

 

New frame, cross members and control arms.

In Oshkosh and Meritor's cases, they were a newly designed HMMWV compatible chassis. Meritor went with their own powertrain and suspension setup [and eliminated the geared hubs] and OshKosh took their Tak-4 system and combined it with a smaller CAT heavy diesel drivetrain. Those aren't available for purchase. They were pitches to the DOD to let them know they could take over HMMWV production from AM General if required in the future.. plus give recapitalization options.

That being said, the 3 section ECV/GV frames may have a higher capacity than 12800 lbs but I'd have to look it up.

 

Thank you very much for this detailed info!

I guess ECV ist exapnded capacity? I heard they use a 3-piece frame, sounds a bit like an idea that maybe troublesome with rust.

But any detailed info/measurements on any frame would be welcomed!

So the oshkosh/meritor frames are NOT just further improved ECV-frames, but truly new frames? Sounds reasonable, since the Meritor version is listet with an even higher GVW of 21.000lbs:

http://graphicvillage.org/meritor/SP12160.pdf

But is it possible to ones hands on an 21000lbs hummer? Would be an awesome basis for a heavy duty traveling vehicle!

 

I dug up an 18,500 GVW chassis from AM-General it looks like they turned their HMMWV compatible BRV-O truck into another product:


The chassis mount points seem similar but there are different control arms and bigger geared hubs.

Anyways, the ECV frames are 3 sections to allow for faster rebuilds, rust wouldn't be my concern any more than the standard design in my experience.

If I required 18-20k GVW+ in an off road vehicle, I'd go the route the US forest service does for its BLM firetrucks and get a 4x4 or 6x6 International Workstar chassis with CTIS/Hutchinson wheels and go from there [some companies build out heavy duty rv's like this]. Either that or get a modern late model unimog or something that was built for that.

The HMMWV/H1 was originally built for 7000-10k GVW and it does well at that range, as the military found out the more crap you bolt to it, the more of a dog the truck becomes and the less mobility you have.

As for buying the extended capacity vehicles.. its a toss up. US surplus a few people got the 16k frame/chassis setups via military surplus and custom built their own trucks but its going to take connections and $$$$ to build it up from the ground up.

 

Not sure if my english serves me well here, but what did you dug up? I see the video where the special chassis is shown, but i am not sure that's it.

The thing that's awesome about the idea of a true 18.000lbs hummer (not something with just added plates like the ECV) is that you would have a vehicle capable of handling really heavy loads while also being able to drive fast.

Any commercial truc like the International workstar uses an open c frame (flexible, not good for speed) and axles+leaf springs (really bad for speed)

Sadly only the military is going for heavy+fast, since they need it the most.

So there is no way to get ones hands on one of those 21000/18500 hummers?

 

No. Unless you want to put in a order to AM General directly. And AMG historically only wants to deal with large orders with governments.

Keep in mind most HMMWV's out there in civilian hands are 7,000-10,300 GVW trucks. Few are 12K trucks let alone anything past that.

I don't see a point going past that because the drivetrain/cooling system wouldn't handle the extra capacity, you would need to design a new truck around the chassis which is what the MPT is.

 

So how many of the 18500 oshkosh-humvess or 21.000 meritor-humvess are even out there? Probably very few and those will end up in the hnds of pretty wealthy collectors i assume.

Would still be interesting to get some measurements to compare the chassi, i mean from 10 to 12 to the new 18.000 frames.

The modern aged Ford HD frame is 240x90x4.5mm in the mid-section, which is quite beefy. I guess the original hummvee frame was smaller, but the new meritor frame would have to be even stronger.

 

H1/HMMWV [m998A2 at least] frames.. the 10 and 12k frames are generally 1/4" HSSS. About 6.35mm in thickness. Boxed frames, rear bumper, and cross members.

I've had my cross members modified with an extra 1/8" steel washers around the control arm bolt holes, additional gussets welded around the suspension pockets, and boxed in the bottom of the cross members, with holes to allow water draining.

 

Can you elaborate on this measurement?

6+mm thickness is quite a lot for a boxed frame, but if that's only due to doubling metal sheets it might not be stronger than the 4.5mm on the ford HD frame.

Do you got the height and width? This should be lways the same for alle frames, or i guess the rest won't fit.

 

H1 / HMMWV frame rails are made out of one-quarter inch thick high strength structural steel. And it's not from doubling. [The doubled up sections on top and bottom of the frame rail would have a 1/2" partial overlap if you want to consider that] The vehicle was made to be airdropped something that's not a requirement for domestic pickup trucks.

The frame rails on my truck is 1/4", the rear bumper is all 1/4" box, all the chassis/bumper/body mount/shock/spring mounts are all 1/4", the lower cross member pockets are 1/4" The cross-member itself may be a mix of 3/8 and 1/4" steel. I remember when I went and rebuilt my frame I welded in more reinforcements on the stock cross members. The non-winch bumper I have in the front is 3/8" steel. Control arms I'm not sure of the exact thickness it's partially cast, about 3/8" there with some sections being more than 1/4" thick. The airlift hooks are 1/4" steel since its ties into upper control arm pockets at the frame, with solid steel bar stock for the loop.