• Steel Soldiers now has a few new forums, read more about it at: New Munitions Forums!

  • Microsoft MSN, Live, Hotmail, Outlook email users may not be receiving emails. We are working to resolve this issue. Please add support@steelsoldiers.com to your trusted contacts.

M35A3 Owners unite

Z71

Member
145
2
18
Location
FL, USA
I do not own an M35A3, but am thinking about getting one (possibly M109A4). Is it true that they use 15W40 motor oil for engine, transmission and the transfer case in that truck? What maximum sustained highway speed is this vehicle capable of without overreving the engine with standard size tires? Mileage for M109A4 at 50 MPH road speed?
 

Timberwolf22

Member
154
24
18
Location
Kenett Square PA
Z71 I had the same "discussion" M35a3 or M109a4...... I ended up putting a S280 shelter unit in the bed of my M35a3 truck. I leave it there semi-permanent but IF I ever want to remove it I have that option and go back to the M35a3 flatbed.... with an M109a4 you are always a box truck.

IMG_2226.jpg

It might also help that my brother owns a M936 wrecker and the crane is handy at moving the shelters around.

For the other info..... my truck has a top speed of 54MPH but that pulls way to many RPM's so I usually drive around at 50MPH and watch everyone pass me. Sure I have looked at the "turning up the fuel" threads, different transmissions, and even the overdrive option. In the end I came to the realization that if I need to go faster then I need a different truck. She does what she was designed to do and does it well but that's not 65MPH.... and honestly I don't think I want her going much faster.

One day when I get ready for the "Larger Tires" I may pick up a few MPH but until then my motto stands .... "they go fast I go anywhere".
 
Last edited:

Z71

Member
145
2
18
Location
FL, USA
Thanks for the reply, do you happen to know about the same type 15W40 motor oil used in engine, transmission, and transfer case in this truck?
 

rustystud

Well-known member
9,280
2,987
113
Location
Woodinville, Washington
Thanks for the reply, do you happen to know about the same type 15W40 motor oil used in engine, transmission, and transfer case in this truck?
The transmission will use "ATF" Dexron and the transfer case will use 80/90w gear oil. Some people have gotten away with using Hydraulic oil ( 15w) in the transmission but Allison recommends "Dexron III " or better in this transmission.
 

SRB1976

Member
317
9
18
Location
Hanna, Wyoming
The transmission will use "ATF" Dexron and the transfer case will use 80/90w gear oil. Some people have gotten away with using Hydraulic oil ( 15w) in the transmission but Allison recommends "Dexron III " or better in this transmission.
The military used 15w40 in the trans for some odd reason. Mine still has the oil in it. Should I flush it out and replace with trans fluid?
 

Mig1965

Member
Steel Soldiers Supporter
31
0
6
Location
Vero Beach, FL
I do not own an M35A3, but am thinking about getting one (possibly M109A4). Is it true that they use 15W40 motor oil for engine, transmission and the transfer case in that truck? What maximum sustained highway speed is this vehicle capable of without overreving the engine with standard size tires? Mileage for M109A4 at 50 MPH road speed?
Yes, 15W40 in both the Engine and Tranny....Engineered to work by people smarter than we so save yourself a possible failure and stick with this combo. Look for earlier threads on this when others went to a Dextron type of solution.

Transfer Case - See page 3 of this TM http://www.jatonkam35s.com/DeuceTechnicalManuals/LO9-2320-386-12.pdf
I'm 99% sure but still confirming this is the replacement...http://www.amsoil.com/shop/by-product/gear-lube/synthetic-80w-90-gear-lube/

Here's a link to TMs (Technical Manuals), mostly on A2, some crossover, but has five good TMs just for the A3.....http://www.jatonkam35s.com/jatonkaM35sTMdownloadpage.htm

Max HWY speed with the stock super single 14.5/20 is truly 50 MPH, so if you're going to travel any sort of distance on regular basis but want this type of model truck, I'd consider going with a newer M92X series 5ton.

Mileage...I think I saw 8-10 MPG in one of the TMs. I'm getting around 10-12
 
Last edited:

Timberwolf22

Member
154
24
18
Location
Kenett Square PA
For mileage on the M35a3 I am getting around 10-12 as well.... depends on if the shelter is in the bed and when I also tow the M105 trailer.

For me the M35a3 was the "right truck" - wanted an automatic, the power assisted steering, the dual brake system and super singles.

In PA there are DL requirements for the M923 5-Ton due to size/weight and air brakes.

I don't think I was ready for a 5-ton then...... I might upgrade to the larger truck but due to the PA CDL requirements I am holding off.
 
Last edited:

Mig1965

Member
Steel Soldiers Supporter
31
0
6
Location
Vero Beach, FL
For mileage on the M35a3 I am getting around 10-12 as well.... depends on if the shelter is in the bed and when I also tow the M105 trailer.

For me the M35a3 was the "right truck" - wanted an automatic, the power assisted steering, the dual brake system and super singles.

In PA there are DL requirements for the M923 5-Ton due to size/weight and air brakes.

I don't think I was ready for a 5-ton then...... I might upgrade to the larger truck but due to the PA CDL requirements I am holding off.
I'm always thankful I live in Florida when I hear about the northern DMV regs. No CDL for the 5 ton.
 

rustystud

Well-known member
9,280
2,987
113
Location
Woodinville, Washington
The military used 15w40 in the trans for some odd reason. Mine still has the oil in it. Should I flush it out and replace with trans fluid?
I would. I served my apprenticeship at Neils Detroit Diesel working on Allison transmissions. I know this particular transmission very well. The only problem you could have is since it has been running this heavier oil is the damage to the clutch discs. Now if you go to the original oil you might get slippage since the discs are saturated with the heavier oil. Right now thinking about this I would go with a 15w hydraulic oil for a few thousand miles and then transition to the Dexron oil. Or just keep the hydraulic oil in it. No matter what anyone says, engine oil in a auto-matic transmission is not good for the longevity of the unit. The reason the military did this is because the "knuckleheads" driving the trucks couldn't figure out what oil to use so they went with just one oil. Pretty hard to mess that up. The military didn't care about transmission life, they had plenty spares to use. We don't.
 

Mig1965

Member
Steel Soldiers Supporter
31
0
6
Location
Vero Beach, FL
I would. I served my apprenticeship at Neils Detroit Diesel working on Allison transmissions. I know this particular transmission very well. The only problem you could have is since it has been running this heavier oil is the damage to the clutch discs. Now if you go to the original oil you might get slippage since the discs are saturated with the heavier oil. Right now thinking about this I would go with a 15w hydraulic oil for a few thousand miles and then transition to the Dexron oil. Or just keep the hydraulic oil in it. No matter what anyone says, engine oil in a auto-matic transmission is not good for the longevity of the unit. The reason the military did this is because the "knuckleheads" driving the trucks couldn't figure out what oil to use so they went with just one oil. Pretty hard to mess that up. The military didn't care about transmission life, they had plenty spares to use. We don't.
Very true. Looks like you are definitely the man here. I've just hit 2500 miles but would like to plan for the move to Dexron if it will definitely keep the tranny running at 100%. Is there a procedural doc or discussion with specific steps that you could point me to?
 

rustystud

Well-known member
9,280
2,987
113
Location
Woodinville, Washington
Very true. Looks like you are definitely the man here. I've just hit 2500 miles but would like to plan for the move to Dexron if it will definitely keep the tranny running at 100%. Is there a procedural doc or discussion with specific steps that you could point me to?
Sadly there isn't one. This doesn't come up in the civilian world as they all use ATF in the transmissions. I have seen it though since I have dealt with it in the Marines and in warranty work at "Allison" . The problem is the clutch discs themselves. They are actually made of organic fibers ( most use impregnated paper ) which absorb the oil used in the transmission. Some use a Kevlar material like our little Allison's do which still absorb the oil just not to the extant of the other types of clutch discs. So the trick is to get out the "old" oil and let in the new oil. Since engine oil is much heavier then ATF it will be very hard to get it out of the clutch fibers. That is why I said to use Hydraulic oil first since it is heavier then ATF but lighter then engine oil. After changing out the oil, I would run the truck for at least 2,000 miles. This will let the heavier oil have a chance to get out of the clutch fibers and let in the lighter Hydraulic oil. Then if you want, continue on to using ATF at your next oil change out. Like I said in the last post, you can just continue using the Hydraulic oil instead. It will last much longer then using the engine oil.
 

Mig1965

Member
Steel Soldiers Supporter
31
0
6
Location
Vero Beach, FL
I do not own an M35A3, but am thinking about getting one (possibly M109A4). Is it true that they use 15W40 motor oil for engine, transmission and the transfer case in that truck? What maximum sustained highway speed is this vehicle capable of without overreving the engine with standard size tires? Mileage for M109A4 at 50 MPH road speed?
Z71, I just listed mine in the Classified section.
 

Timberwolf22

Member
154
24
18
Location
Kenett Square PA
Looking for some input on a M35a3 Front Winch issue.

So I have an M35a3 and my front winch will not engage and spool in.... so let's go thru what I have already been troubleshooting.

Broke out the TM and followed the step by step winch engagement steps..... no luck.

Made sure the Hydraulic reservoir was full and no leaks = check
Started vehicle with vehicle in neutral with parking brake engaged
Checked air pressure - good

Pulled out drum lock knob and I could free spool out the winch cable so no issue with a frozen winch drum
Moved winch clutch lever to IN
Engaged winch control lever in cab
Moved winch control switch to IN = Nothing

Tried variations on all of these combinations such as drum lock out or locked in, moved the Winch clutch to OUT and back to IN.

I could see the air controlled hydraulic "piston" right behind the reservoir move up and down but nothing else.

Yes I hit everything with a hammer.... multiple times.

Does anyone's Hydraulic pump engage and make any "noise"

Curious if my fellow M35a3 have any thoughts on the Winch issue?

I will be at Sussex if anyone wants to help and take a look at the Winch.
 
Last edited:

househaunter

New member
5
0
0
Location
Denver, CO
I had the same problem with my A3. Turns out, the air line to and from the "PTO" engagement lever on the shifter tower had been looped through with a 1/4" union air fitting bypassing the switch. Would have never guessed that and it took me some time of chasing things down. Could be worth a look in there.
 
Top