M35A3 Transmision question.

[glcaines]

I wish you good luck with your transmission. I have now decided that your A3 is the one I was trying to get, but you outbid me and I went after the one I won. It could have been me with the transmission problem. Was yours the one with the good cargo cover? I don't know what the proper pressures are supposed to be, but perhaps there is some restriction in the valving causing reduced flow. Just guessing here.

 

[motomacguyver]

I previewed all 4-5 trucks in the lot, and they all seemed about the same to me. It was pretty hard to do a thorough inspection on them all, due to time constraints. And I don't know what could have been done to find aout if there was a bad transmission anyhow. They won't let you take them for a test drive. Yes, the cargo cover was decent, but not mint. I'd be happy to trade you the cargo cover for your transmission, I'll pay shipping.

 

[renovate7]

I just read another post where someone had a loss of power/not shifting right. New fuel filter fixed it. May be a stupid thought but have you changed the filter? You may need max power for a proper shift into 4th/reverse.

 

[Rustygears]

The A3 does not need max power to SHIFT into reverse. The other posts were about the truck bogging down.

 

[motomacguyver]

The Allison Dealer I talked to after the pressure test says. Its my fourth gear clutch pack going bad.

Major Bummer. He figures the old oil may have been building enough PSI to let the transmission work but it would have failed pretty quickly.

 

[glcaines]

The Allison Dealer I talked to after the pressure test says. Its my fourth gear clutch pack going bad.

Major Bummer. He figures the old oil may have been building enough PSI to let the transmission work but it would have failed pretty quickly.

Are you going to try to rebuild it yourself or pay someone?

 

[motomacguyver]

Are you going to try to rebuild it yourself or pay someone?

I'm pretty sure I wil remove and replace it myself, but the actual rebuild is Not something I have done before. I might tackle it if it's not to tough, but the parts are $$ and I would hate to do all that work and have something go wrong. There is an authorized allison dealer in this state, They would do the torque converter testing, dyno test, and a 6 mo warrenty. This is what I'm leaning towards.

 

[tbone69]

I talked to a mechanic today that went to school at Allison years ago and is familier with the AT1545. he said it was designed to work with 15-40w oil. if the fluid and filter is kept up, this setup should last many years and thousands of miles.seems several people are having trouble after changing fluid types. are there lots of failures leaving the 15-40w in place?

 

[glcaines]

I talked to a mechanic today that went to school at Allison years ago and is familier with the AT1545. he said it was designed to work with 15-40w oil. if the fluid and filter is kept up, this setup should last many years and thousands of miles.seems several people are having trouble after changing fluid types. are there lots of failures leaving the 15-40w in place?

Your mechanic friend is incorrect. I talked directly with Allison and they definitely recommend using Dexron III or TranSynd and purging the motor oil. However, some other Allison transmissions are recommended to use motor oil, just not the 545 or 1545 transmissions. You can also read this by going to the Allison website. I have attached one Allison document on the 1545 which shows Dexron III is recommended. I used Dexron III which also had the C-4 certification.

 

[Rustygears]

My experience & research is exactly the same as above. The 545 and 1545 will work with 10w40 oil, but it is not recommended. If MO is used, the performance is lower and the service life is much shorter. The only fleet that uses MO in these trannies is our rich uncle sugar who can afford to dump a vehicle well before its service life is over or spend $$$$$$ on premature drivetrain replacement solely to have the concept of pouring one fluid into any hole on the vehicle. Sad to say they either think our soldiers are that dumb or that they actually are.

The ones I've worked with were some of the most clever guys I've met, even if some fancy school didn't give them a worthless piece of paper to prove they were clever.

I'm surprised they didn't use 10w40 in the diffies, the transfer case and the brakes for the same idiotic reason. Hey - better check and change those fluids too - ya never know.

 

[ApopkaFL]

I found a site that has the A3 transmission for $600.00 ARMY 6X6: PARTS I hope this helps.

 

[flyxpl]

I found a site that has the A3 transmission for $600.00 ARMY 6X6: PARTS I hope this helps.

Sounds like a very reasonable price considering all the A3 bashers say that these trucks will cost you a fortune if they break .

 

[glcaines]

Sounds like Army 6X6 bought them used since the ad says tagged as "good". I would be more comfortable with a take-out that I saw function before I made the leap. That being said, $600.00 is a good price if they work, compared with rebuild costs.

 

[ApopkaFL]

How many people do you know that is going to part out a A3?

 

[glcaines]

How many people do you know that is going to part out a A3?

Fortunately, not many are being parted out since they are rare. I have seen some ads however about A3s being parted out. It appears they were very rusty corroded trucks. I understand that not many of the A3s are being sent to allies overseas. Although they didn't make that many A3s, as more enter the market the price should drop and you will likely see more being parted out. I hope the values stay relatively high however as a lot of guys have invested a lot of money in the trucks. I predict the value of A3s to decrease as more are released and then rise again as the supplies dry up from the government.

 

[mktopside]

For $600 I might just buy one. I've blown more on a whim before so it can't hurt. Hummmm

 

[swampzr2]

I did the 15 w 40 swap to Dex III and mine still seems to have that clunk when down shifting.

What trans upgrade are The A3 people doing to get 5th gear and higher top speed? Sounds like a good time to look at this option. I wish mine had a higher top end.

 

[glcaines]

I did the 15 w 40 swap to Dex III and mine still seems to have that clunk when down shifting.

What trans upgrade are The A3 people doing to get 5th gear and higher top speed? Sounds like a good time to look at this option. I wish mine had a higher top end.

I'm assuming you did the drain and refill procedure? How many times did you drain and refill? Did you drive the truck between drains? Mine still clunks when downshifting, but it is not nearly so loud and clunky as with the MO.

 

[swampzr2]

I did 2 drains, and just drove it up back and forth in the driveway. I shifted into N, P, R, And D multiple times and let it idle for a long time. Probably could drain it again since I put 100 miles on it since then.

I'm assuming you did the drain and refill procedure? How many times did you drain and refill? Did you drive the truck between drains? Mine still clunks when downshifting, but it is not nearly so loud and clunky as with the MO.

 

[motomacguyver]

What trans upgrade are The A3 people doing to get 5th gear and higher top speed? Sounds like a good time to look at this option. I wish mine had a higher top end.

I also, "half donkyied", looked into the trans swap. Seems like an Allison MD3060 would be the way to go. With double overdrive, higher HP and torque ratings, and only about a 2 inch length difference. (With OUT the PTO option, which isn't used on the A3) However this is a full electronic trans, so you would need all of the wiring, neutral switches, reverse switches, "black box" etc. A local heavy truck parts bone yard, has 2 that haven't been removed from the garbage trucks they came in on.

The bone yard wants 3500$ for the Trans, 1500$ for the core, and 1500$ for the complete wiring harness. He said he would knock off the core charge, so 5000$. Both trucks had 175k+ miles on them. I Know those are some hard miles, because every time my garbage guy comes by, he is darn near running. So...I have a hard time spending the time and $ to put in an unknown/worn trans.

These things are also 3500$ to have rebuilt. So IF you could get the wiring only, AND a matching, rebuilt 3060 Trans. (5455$, I checked, http://www.utxchange.com/faq/transmission-specifications/md-3060/) It would cost~ 7000$. Not including shoehorning the thing in there and figuring out the Mounting points, wiring hassles, shift tower, and the differences in length (the drive shaft that goes from the tranny to the transfer case is mighty short.) Oh and also figure out your torque converter mounting, plumbing, AND make sure the torque converter ratio is the one we need. (From the donor vehicle) AND if it’s a 12 volt system then we need to put in a converter. (Not sure on this one)

This sounds like a BIG project to me, probably bigger then bobbing one. Especially since this is "uncharted territory" as far as I can tell.

The good news is that If someone decides to do this, I think the SAE-2 Trans mount of the 3060 may bolt right on to the cat 3116 engine flange.

I also PM'ed the fellow in the "A3 owners unite" thread, that talked about this, and haven't gotten a reply yet. (1.5 weeks).

Would this be nice…? YOU BET. However it’s also probably a 40-80? Hour job. So... for now, I am going to check out the 600$ "used" AT1545 with a VERY skeptical eye. And will probably go with a certified Allison, Dyno tested, and 6 mo. warranty rebuilt unit.

I guess if I wanted to go fast I would have bought a motorcycle, with nitrous, for less $.
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