Whatever it is, I cannot find a better picture of it. I've searched high and low.

Dustin I feel your pain as I have certainly not been able to find any better reference either.

Gino I agree with you on this. Also the bars do not line up with either the upper or lower A-arm pivot points in the photographs as they do on the illustration. Oshkosh certainly does offer torsion bar suspension but not on the MTVR. I am thinking they simply use the same torsion bar mounting brackets for these strengthening bars.

I put out a few more feelers. Let's hope it turns up something good.

Gino, y'all don't have any of these on post?

Ok, my Dad talked to his buddy. He said they are torsion bars for the front suspension. He said they service the MTVR every year for the Marines. He is going to get some pictures of how they go into the front suspension, but idk how long it'll be before he sends them to my Dad.

I guess he copy/pasted their convo over to ours.

Nope, the US Army doesn't use the MTVR. They are strictly USN/USMC vehicles.

It will be interesting to see how these work as torsion bars and why they are only on the longer chassis versions.

I was curious. When I worked at Ft. Sill I seen them a lot. But I know the Marines were there training.

I hope we get the pics soon, if nothing else so Michael can add it to his model.

My theory is that they are added to the vehicles carrying a heavier payload, thus a suspension upgrade was needed.

Talked to someone today at Oshkosh Defense. We are going to exchange some images tonight via e-mail. Hopefully by tomorrow we may have the answer.

Often model competition judges are a lot like Drill Instructors; "Close enough AIN'T good enough."

That's awesome! I'm ready to get to the bottom of this.

Mk28 Extended Frame MTVR with winch:





(All photos this post by navymailman )

I put a call into Oshkosh and was lucky enough to find someone willing to take a moment to discuss this. It was confirmed that these are considered torsion bars in the parts manual - used for the purpose of resisting frame twisting and therefore reducing the chance of wheel hop. At this time we are still not sure if these bars are actively connected to the suspension or connected only to the frame and used simply to reduce the chance of frame twist.

In the right side shot, it does look like the torsion bar extends forward of the front frame mount. Interesting.

HIMARS Resupply Vehicle (Mk37):



Now this just might be a vehicle worth modeling!

If you are interested I just designed a set of the mounts in CAD for those torsion bars for my Mk28 conversion. They are the same as those you need. I had them 3D printed by Shapeways and should have them here on Thursday. They are just the mounts - designed to work with 2.2mm diameter rod / tube (I happened to have a tube of this diameter, that's why I designed the mounts for it). The cost of printing the part was about 10 euro +shipping. If you want I can send you the stl file, so that you can order a set for yourself. Of course they are not very difficult to just scratch built, but I was too lazy to do that and preffered to do some CAD work


https://www.shapeways.com/fragments/product?spin=83N9XPSN4

EDIT: I made the part orderable, so you can just order it from Shapeways if you wish.

It does, on both sides. There is another mounting bracket behind the fuel tank and the boarding steps.

Good to know. So the torsion bars do not connect to the front suspension at all. They are there to add strength to the extra long frame so it doesn't buckle or twist under a load. Is that correct?

I would love to see your Mk28 progress Pawel. Any pics or a link to your build?

That is my understanding.



No pics yet at this moment. Maybe I'll take some next weekend.

Guys, having extensive knowledge of the TAK-4 suspension I can say that this torsion bar set up in not connected to either the front or the rear suspensions. These were added to counter the torsional twisting created by the longer frame. Very few TAK-4 suspensions in military use torsion bar set up, almost all are coil over springs.
DJ

Pawel thank you for letting me (us) know about your work. I will be ordering a set TODAY!

Yes, I do realize there is another mount forward behind the battery box. In this one drawing shown below I think they might even be indicating two, albeit narrower, brackets forward.

Actually this drawing is misleading. In reality the middle bracket set on this side is the same width (double) as on the right side of the frame. Just the pattern of bolts on it is a mirror image. And the forward brackets are located pretty much in the middle of the fuel tank length - again on both sides of the frame. My 3D set comes with four identical bracket sets for front and rear and the mirrored parts for middle brackets.

DJ and Pawel, thank you guys for weighting in on this question!

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Pawel, I see you have now earned your CRC accreditation. (Certified Rivet Counter) Congratulations!

Parts now ordered from Shapeways.

Ditto on being anxious to see your work on the Mk28!

At it again! Cutting up this truck.

I had the overall vehicle length correct but had nine inches too much ahead of the rear bogies. And nine inches too few behind the last axle.


Still need to add that nine inches back in at the rear of the frame.

Here is what the MTVR is currently looking like:

I think that nine inches, proportion wise makes all the difference!



Also added the mud flaps ahead of the #2 axle plus some assorted piping and the electro/hydraulic control box between the cab and the LHS.