M915 - what a ride!

[NDT]

Just got back from a 350 mile trailer recovery from Camp Beauregard. Am I tired? A little. Are my ears ringing? No. Is my butt sore? No. I was driving the Cadillac of MVs, the M915A1. I just cannot say enough good about these trucks. 58 mph, 7 mpg, quiet (I got the muffler on finally), fast off the line. Soon to have A/C (thanks dilvoy!) and a radio. M172 trailer pulls like a dream. We'll see how it does with a 50,000 lb tank soon!

 

[velociT]

How's the tranny?

Autos frighten me by nature....

 

[muddog]

Nice looking combo, waiting for the photos with the tank.

 

[Tackettr]

I just helped M1075 move a couple of his. I agree with the above however you do need some weight on the 5th wheel! We were running bobtailed and it was ruff!

 

[NDT]

How's the tranny?

Autos frighten me by nature....

Same proven Allison trans used in thousands of garbage trucks, Greyhound buses, etc. What's funny is it shifts just like it's ancestor, the Hydra-matic 303M in the M135 deuce. Hold on for the 2-1 downshift . . . BAM!

 

[LanceRobson]

They do shift with some, ummm.... authority, don't they? If your not kinda gentle with the fuel it'll chirp the tires without trying.

Nice looking rig.

Lance

 

[M1075]

Just got back from a 350 mile trailer recovery from Camp Beauregard. Am I tired? A little. Are my ears ringing? No. Is my butt sore? No. I was driving the Cadillac of MVs, the M915A1. I just cannot say enough good about these trucks. 58 mph, 7 mpg, quiet (I got the muffler on finally), fast off the line. Soon to have A/C (thanks dilvoy!) and a radio. M172 trailer pulls like a dream. We'll see how it does with a 50,000 lb tank soon!

Thanks for the post! I'm looking forward to getting mine out on the road soon. I have been wondering if the M172 will sit level with the M915 or if it will be a little low in the front. I can't really see any problems in your pics, but it doesn't look like level ground either. How much different was the ride (comfort wise) with the M172 and did you even notice it behind you (M172 is heavy!).

 

[M1075]

More detail on the A/C please!

 

[mudguppy]

what trailer do you have that'll take the 50k# tank?

 

[M1075]

what trailer do you have that'll take the 50k# tank?

M172 is 25 tonner

 

[M813A1]

HEy James you might have to find a M872 or M870 ?? Tri-axle trailer to go with the M915 !!

 

[M1075]

Alas......my M915 is on the block.....$3500.00 as is or $4500.00 with big arsed van trailer.
PM for pics.

Hate to see you sell it. I put one of my M915A1s in the classifieds. You might try the same.

 

[mudguppy]

M172 is 25 tonner

i know, but isn't that overall capacity, as including trailer weight?

i wouldn't put 50k on it. i had one for my M10000 VRF which weighed in at 35k - the 172 seemed quite maxed, given the rate we were going through tires, wheels, brakes, etc.

 

[jasonjc]

The M172 is only a 15 ton trailer Max gross 45,500 net 15,500 = 30,000 load.
The M172A1 is rate for 25 tons Max gross 64,860 net 14,860 = 50,000 load.

 

[NDT]

OK, the A/C is a MTVR kit offered by dilvoy here on the forum. I like this kit as opposed to the Red Dot being offered because it has the slab condenser that goes in front of the radiator as opposed to the HMMWV roof mount condenser type with the 2 parasitic electric fans.

The trailer does sit a little low in the front, maybe 2 inches, not very noticable. It is a M172A1. As far as carrying capability, years ago M172's were coming out of Ft Hood that were big time bowed in the middle. I asked how they got that way. Answer: Transporting M60 tanks around post!

The trailer did help with ride quality somewhat. That part is still un-Cadillac like.

 

[wreckerman893]

I once had the opportunity to convoy from Fort Benning, GA., to the National Training Center at Fort Irwin, Ca.
We drove M915's pulling the three axle trailers the Army had then.
My trailer had two deuces loaded on it and the truck ran great all the way out there.
Our trucks had the 15 speed CAT transmissions in them and would run with the big rigs out on the interstates.
The trucks are very hot inside since you can't get a lot of air through them. New Mexico, Arizona and the desert in California were miserable.
We drove eight hours and laid over in motels along the way.....it took us five days to get to NTC.
I flew back on a cargo plane since they decided to rail most of the equipment back.

 

[M1075]

OK, the A/C is a MTVR kit offered by dilvoy here on the forum. I like this kit as opposed to the Red Dot being offered because it has the slab condenser that goes in front of the radiator as opposed to the HMMWV roof mount condenser type with the 2 parasitic electric fans.

The trailer does sit a little low in the front, maybe 2 inches, not very noticable. It is a M172A1. As far as carrying capability, years ago M172's were coming out of Ft Hood that were big time bowed in the middle. I asked how they got that way. Answer: Transporting M60 tanks around post!

The trailer did help with ride quality somewhat. That part is still un-Cadillac like.

Wow, an A/C would be nice for the summer!

One manual I looked at showed the kingpin height of the M172A1 at 57.375" (I assume this means when level). After checking the trucks, I found these fifth-wheel heights

M915A1 49-51"
M818 53"
M911 64"
M916 65.75"
M920 67.75"

So it looks to me that the M172 will not sit level with any military truck! I do prefer it to be high in the front as opposed to low, though.

 

[rideni]

Alas......my M915 is on the block.....$3500.00 as is or $4500.00 with big arsed van trailer.
PM for pics.

heck of a deal if its around much longer I may have to jump on it

 

[NMC_EXP]

Our trucks had the 15 speed CAT transmissions in them and would run with the big rigs out on the interstates.

Does that CAT transmission have a pneumatic shift mechanism?

I did a significant amount of work for the CAT transmission unit on a pneumatic controller for what was described to me as a military truck transmission.

These controllers were built by one man, in an small room in the corner of the transmission factory.

These controllers were 100% function tested before shipment. When one failed the test he would disassemble it and start replacing the various moving parts and o-rings in the problem area until he found a combination which would work.

I convinced the transmission guys that the o-rings were not the root cause of their test failures. Don't know what if anything they concluded.

It was strange to see this "patient old world craftsman" approach being used in the 21st century. Mass production and interchangable parts it wasn't.

Regards

Jim

 

[NDT]

Does that CAT transmission have a pneumatic shift mechanism?

I did a significant amount of work for the CAT transmission unit on a pneumatic controller for what was described to me as a military truck transmission.

These controllers were built by one man, in an small room in the corner of the transmission factory.

These controllers were 100% function tested before shipment. When one failed the test he would disassemble it and start replacing the various moving parts and o-rings in the problem area until he found a combination which would work.

I convinced the transmission guys that the o-rings were not the root cause of their test failures. Don't know what if anything they concluded.

It was strange to see this "patient old world craftsman" approach being used in the 21st century. Mass production and interchangable parts it wasn't.

Regards

Jim

The M915A1 has an Allison transmission, but the M915, M916, M919 and M920 all had the Cat transmission you are talking about. There are several threads on that transmission here on Steel Soldiers and they all mention that the controller (picture) is the root of a lot of problems with the pneumatic shift system.