Adding an extra axle to an M109A3

Hello everyone, this is my very first post and I'm very excited to be here and hear what everyone has to say... so here it goes. I am in the process of purchasing an M109A3 and would like to add an extra axle. Has anyone ever come across which commonly available axles (off any old truck) will possibly be adequate for this endeavor? Also, if this is just not a possibility, does anyone have any suggestions on where to find axles (where they may be so sold or do I just have to find another truck?)? Thanks for taking the time to read the post... I look forward to your replies!

Any particular reason to add an extra axle ?

I've always thought the 109A3 was rather short, and a third axle would have a hard time fitting anywhere. Surely you don't want to put even more in the back of it do you? As it is, on the highway they are rated for 10k, and that might be somewhat conservative from a axle load standpoint. Brakes however

Then trying looking for a 5 ton van, it would be cheaper and you wouldn't get your hands dirty if your looking for added weight capability.

M820s are neat (5 ton expando van)


note: GL photo

If I were to want to add an additional axle to a deuce, I probably would use a M105 axle and a set of wheels off a M1061 trailer.

The reason for this tire /wheel combo is that the tires are 16.5 inch diameter so they would fit in the space where the spare tire mounts. I'd use a combo leaf air bladder for the axle attachment, and you can hook up the brakes.

If you need more load capacity than a deuce, look for a 5 ton truck. The M820 comes to mind for an enclosed truck of a 5 ton rating.

Welcome to the site! Normally a 1st post is reserved for complaining about GL or EUCs.

How much gold will you be hauling in your 3 axle 109 and how can I help?

Seriously though - if you need it there and it can be done the folks here are the people to ask.

Thanks or the warm welcome! I don't want to add an extra axle merely for weight purposes but rather for traction. I'm planning on using this baby for camping in frozen terrain and adding an extra axle would help immensely when it comes to all terrain capabilities. I thought about a 5 ton van, but then realized that the headache of a CDL would stop me from having one of these vehicles for much longer than I intended it and I just don't have the patience to wait (I'm too excited!), although to be honest I will probably eventually end up buying one. Again, thanks for all the replies, comments are still welcome .

chains will help more then a extra axle, the extra axle will spread the weight , giving less traction, more flotation

I also would like to add another steering axle behind the front axle to help with traction/flotation in the front. In the meantime, I will run 395s.

Drop the extra axle idea and opt for some better...lugger type tires/chains as Ron said.

That 3rd axle ain't gonna work for ya IMO. Steering issues etc will cause you headaches ya don't want.

Those trucks are designed and tested...and proven to work in all kinds of terrain...trust me..take the better tire/chain approach first...if that won't work for you then consider other options.
By the way...welcome to the family of OD Addicts.

I hate to say this but if you plan to use the truck to drive on snow or ice you will ahve a problem. If you plan on adding an axle you will probably have to lengthen the frame. Then you have to figure how you will power the axle, if the axle is not powered it will cause extra drag, also the extra axle will affect over obstacle ground clearance. I have driven in winter conditions all my life and the more axles the better chance you'll get stuck. Look at the extra weight you are putting on the truck.
We have an M109a3 that we drive in snow and ice and the best traction aid we have are Michelin XYL with deep lugs. Good Luck in your quest

Look at a set of tracks for the truck. Tandem Axle Track Systems - Right Track Systems Inc.

This is just another one of those threads with the most outlandish topic. Sure its nice to talk and think how cool it would be to have a deuce of whatver with 3 rear ends..chances are it will never happen..plus itd be pointless..

I seriously dont think ur truck would turn anymore. ..itd just go straight cuz theres no way ur two lil wheels up there are gonna compete with all 12 or 6 massive meats in the rear. and the suspension system would be a complete nightmare. Gotta keep at least somwhat realistic..

Like some huge agressive meats and some chains if need be..OH and be sure to have a winch if ur gonna go in snow.

rivired said:

This is just another one of those threads with the most outlandish topic. Sure its nice to talk and think how cool it would be to have a deuce of whatver with 3 rear ends..chances are it will never happen..plus itd be pointless..

I seriously dont think ur truck would turn anymore. ..itd just go straight cuz theres no way ur two lil wheels up there are gonna compete with all 12 or 6 massive meats in the rear. and the suspension system would be a complete nightmare. Gotta keep at least somwhat realistic..

Like some huge agressive meats and some chains if need be..OH and be sure to have a winch if ur gonna go in snow.

Click to expand...

If it had an additional STEERING axle, it wouldn't have a problem steering, would it? Search XM410

It wouldn't be pointless. It has often been pointed out that the tire to weight ratios in a deuce are very lopsided. 8 tires in the back with a bed sitting on them. 2 tires in the front with the engine, trans, case, fuel tanks, cab, etc. on them. In soft stuff, the front will sink. A deuce is not unstoppable, and I venture to say less capable than a HMMT or Tatra.

ya ur right its way less capable..so why would u try and turn it into one..a tatra body ..and everything else for that matter are tottaly diff from a deuce..where would u POSSIBLY put a nother axle? right under the cab? are u gonna chop the tool box and battety box off? are u gonna put a 12 inch body lift on the cab just to fit the tires and allow for articulation? how would u fit 2 sets of leaf springs under it? its simply not long enough.

Its just the most outlandish thing ever. it would take SO much money and SOOO much fabrication itd be insane..and not cool insane either..ud have a monstrosity..

Like if i had the choice of a practical tatra(if theres such thing size wise) or a deuce..id take the tatra..but i cant afford one..BUT if u can afford to attemp to turn a deuce into one then go for it..

Well, I do just happen to run a machine and welding shop....

Ever see the boober deuce they guy took the steps off of and relocated the battery and toolbox up in the back for clearance? Think it had no bed, strictly offroad setup. Wish I could find pics. I think it had 49" tires and a lift of some sort. I don't see it as being impossible.

AHA! found it.




I think a guy could fit another axle (with smaller tires) in there.

On snow and ice, you need two things to get traction - weight and grip. For weight on a 109 rear, take the middle four tires off, chain up the axle and put the tires in the back - Bjorn kindly gave us the weight of each tire&wheel as 195 pounds, so that will add 780 pounds to the weight on the remaining four back tires. For traction, tire design or chains is the only methods that will work - pick your poision! If you want to travel on sand or mud, you need float - less weight per square inch of tire contact - so another axle or duals on the front axle might be a method of acheiving that goal.

Remember a couple of things. 1. These machines have been going over all types of terrain for well over 50 years. The Canadian version of the deuce has millions of miles driven over snow and ice, as do most of the ones the military sent to Europe or were located in our northern states. No automotive designer has come up with a better idea (engine, cab and steering up front, cargo in back) yet.
2. Just because someone comes up with an idea, does not mean it is practical, even though it's doable.
3. Beware of unintended consequences.

How does this help the website?