HELP ME! I'm going MAD!

Libelula my prototype LMTV is an incredible vehicle!

I know she loves me! She got my buddy Sethzilla & I from Connectiut back to the central coast of California. However, i've had nothing but problems with the prototype Allison MD 3070. Over the last few weeks I've chased wires and tested wires from dawn till dusk for days, then determined that the ECU was bad!

To make a long (and to me painful) story short...I send the ECU off to the Guru's and got word today...

They have NEVER seen anything like it! AND Allison references nothing retaining to the numbers of the ECU or the transmission. YUCK!!!!

So! please give me you opinion!

Do I throw myself at the mersey of Allison and beg them to sell me the components (soliniods, valves, wiring harness, and ECU = +/- $ 10K) and The correct program ( that will probably need Condalizza's blessing)

Or do I say...

FU@K the BULLSH*T!

And go 100% MECHANICAL!!!!!!!!

Heck I could probably buy a new Marmon Herrington T-case for less than Allison would want for their bits and pieces.

I am going to build this truck into my next "expedition truck" and plan on going into the Baja outback for extended periods and I don't carry a sat phone.

RE: HELP ME! I

Who is your "guru"? If you give me all the #s off the dataplate, I'll get with my "guru" and see what he can make of it. He has worked for Allison for 20 years.

RE: HELP ME! I

Mechanical!!!!!!! The hell with automatic transmissions!!!

RE: HELP ME! I

go 100% MECHANICAL!!!!!!!!

Click to expand...

RE: HELP ME! I

My guess is that he is still talking about an automatic, just without the electronic control gizmos. BTW, an automatic is preferred offroad by some for smoother operation.
The 6-speed Allison auto in the xm757 has very small increments (about 1.4:1) and the 2-speed transfer was eliminated.
Top speed in 4th gear is like 25 mph.

RE: HELP ME! I

Mechanical with standard tranny is the way to go...millions of WWII trucks set up that way lasting 65 years...no electronic stuff to corrode and no clutch packs to burn and solenoids to clog. etc

RE: HELP ME! I

The easiest swap would be to go with a non-electronic Allison auto. You could probably find one with the same case length and ratios. The MT654CR in the 939-series trucks has been durable. I have seen them on eBay. John Winslow had a HEMTT Allison HT740D tranny the last time I was at his place.

Thanks Guys!!!!!

My Allison Guru's are John & Jim at Dartco in Anaheim

Here are the numbers off the transmission

Serial no. 6510000538

Part no. 29500226
89-27

Any help will be GREATLY appreciated!
*****
Unless I am touched by a miracle...I'm think I'm going 100% mechanical! I am so frusterated with the whole Allison "sorry no data available" attatude that I think I'll even shine their non electronic models. Only time will tell!

WHOA WHOA, IF YOU DO THAT THINK FIRST.

Alright got your attention. Did you ever check the supply voltage to the TCM? If it's even a LITTLE off its gonna make the TCM act haywire. This is a problem on BRAND NEW FMTVs, where they act totally out of control with a TCM failure everytime they are started even though they pass diagnostics when you try to trace the problem.

If you got the Allision touchpad with the electourescent display ((blue numbers not the red led)), then you need to press the up and down arrows and hold for three seconds, the transmission will go through a series of checks and then it will spit out codes at you, for this you'll need a TM, yes I know the XM is different, but really it's not. There's almost no chance your TCM is bad, it just doesn't happen. I've worked on about a 100 different FMTV/LMTV trucks with electrical gremlins, and almost always its related to a bad ground somewhere.

Now remember that the Cat motor in that truck communicates back and forth with the transmission and unless your prepared to reprogram it you'll have less than satisfactory results swapping a 900 series trans into it.
Key things here is that a multimeter might say a ground is fine, which sure at a milliamp it is but resistance would be enough to reduce voltage to the TCM at a higher amperage, the only way to know is to tap the supply voltage to the TCM and find out.

If the TCM turns the touchpad on and cycles the mode light AND shows 8 8 on the display for a few seconds, it has passed its self test. S&S nearly got their contract pulled last year over this very nonsense after the mass success of the MTV the marines use, and at a lesser cost than the S&S FMTV vehicles. Oshkosh's truck has greater complexity than S&S so there is no real excuse to why that can't get it right the first time.

I'm gonna ask one of the other guys in the motorpool in the morning, he has dealt with more TCM faults than I have and knows most codes by heart.

Go mechanical all the way.. Electronic stuff sucks and will leave you walking in the desert to die.. I know some of you guys will disagree but I dont ever like being at the mercy of some little electrode you cant ever find or a code you forgot while cooking in the middle of the desert.. Duct tape and chewing gum will fix most mechanical problems and get you home.. hehehehehee

army_greywolf said:

WHOA WHOA, IF YOU DO THAT THINK FIRST.

Alright got your attention. Did you ever check the supply voltage to the TCM? If it's even a LITTLE off its gonna make the TCM act haywire. This is a problem on BRAND NEW FMTVs, where they act totally out of control with a TCM failure everytime they are started even though they pass diagnostics when you try to trace the problem.

If you got the Allision touchpad with the electourescent display ((blue numbers not the red led)), then you need to press the up and down arrows and hold for three seconds, the transmission will go through a series of checks and then it will spit out codes at you, for this you'll need a TM, yes I know the XM is different, but really it's not. There's almost no chance your TCM is bad, it just doesn't happen. I've worked on about a 100 different FMTV/LMTV trucks with electrical gremlins, and almost always its related to a bad ground somewhere. .

Click to expand...

Never had this problem with an M35.

Would the Army actually ever consider the Marine MTVR for a truck in their fleet?

Never had this problem with an M35.

Click to expand...

You've never had a bad ground? Yours must be the only M35 that hasn't!... If you search the archives, you'll see that bad grounds are one of the most common problems with the M35, causing everything from lighting problems to melted battery terminals to non-charging alternators and non-running fuel pumps.

Jon

Hmmmm

JDToumanian said:

Never had this problem with an M35.

Click to expand...

You've never had a bad ground? Yours must be the only M35 that hasn't!... If you search the archives, you'll see that bad grounds are one of the most common problems with the M35, causing everything from lighting problems to melted battery terminals to non-charging alternators and non-running fuel pumps.

Jon

Click to expand...

Well all you have to do is undo it clean it up and keep going.. Plus the truck will still run without any of the stuff you mentioned going bad even the fuel pump.. Dont need any electronic to make her go,shift,start when stranded in the middle of nowhere..
Modern day missed the KISS theory.. Keep it Simple Stupid..

RE: Hmmmm

Grey Wolf thanks for the excellent review of the FMTV problems I hate to see them replacing the 900 series which got me through three combat tours.

On ground issues I concure I had an old Dodge Dart 1963 that had an excellent 170 slant six and three on the tree one day on the road it just stopped dead. After an hour I finally found that the ground to the condensor in the distributor was corroded and after cleaning that it ran like a top I still regret driving it to the junkyard years ago.

Libelula Lives!!!

Funny that the thread about my transmission issues "came back to life" the day after I got libby running again.

Well guys...

I stuck with the allison MD3070. The reasons are many, here are the big ones:

* Due to the MD3070's top 2 gears being overdrive (and her top speed being 56 mph), i would have had to change the ring and pinion gears. I learned that the axles were european rockwells (double reduction) and that i might NOT be able to find other ring & pinion gears.

*The fitting of the divoursed transfer case would have entailed me cutting, hacking, & moving several frame components. I design & prototype complicated mechanical gizmos for a living and have a 5 axis cnc machine shop, so the change was in my capacity. However, I felt that I would be messing with an entregrated design that was well thought out...Just with a faulty component.

Here is a sample of the "hell" I went through to Miss Libby back up and going...

After exausting all leads trying to find anyone that could repair the prototype ECU (the brain), I convinced my local Allison dealer to lend me a WTEC II ecu to test my system with (I actually borrowed 3 of them over a 2 month period). I found that I had continuity on all the wires from the plug on the side of the trans case to the computer, but got no resistance from the solinoids! I got the guts up and pulled the pan & control unit. I then tested the solinoids on the bench and got resistance! I then plugged in the cable again and got no resistance. At that point I had to remove the bed off of Libby to get to the F'en cable. I then repeated my cable testing on the bench...AND still got no results!!!
I was at wits end when I decided to test the connection between the plug on the cable and and the connector that goes through the trans case...

Well low & be HO! the pins in the damn plug were not contacting! I ordered up another plug and at the same time was able to find a used WTEC II ECU (VERY RARE). I put everything together and bench tested it all and IT WORKED! YEAH!

But...That was when the real hardship began!

Excited that I'd be driving libby soon, i ordered the pan gasket set red lable Saturday delivery (costing me a meer $220 for 3 gaskets). I cleaned off the old gaskets and threw them in the trash then opened the new gasket set then placed the first gasket on the pan and freaked out when I saw that the gasket was 1.5" longer!

The following I called my true "GURU" back east and he broke the bad news to me...The gasket set i had was for the oldest MD3070 that Allison ever commercialy offered and I was up sh*t creek without a paddle. OH JOY!
I put my old brain in gear & then dug all the old gasket peices out of the trash mounted them on a peice of masonite then took my od gaskets & the new ones to a local reprographics house then had them all scanned. I then went and put the scanned images through a raster to vector converted, then up the converted images into my CAD system. It took me about 25 hours to REDRAW the gaskets that were correct to MY pan! I then had a laser cutting house cut me the correct gaskets. MAN WHAT A PITA!!!
Last week I i mounted the pan checked the wires again. All was good!

OR at least that was what i thought...

On her first test drive I turned on the light circuit so that I could have turn signals then smelt smoke coming from the wires going into the ECU! I shut down and went to pull the plugs out of the back of the ECU and they were too hot to grab!
Well after all that I'd been through...What's a couple of burnt fingers???
I pulled out my multimeter and quickly found the source of the problem ( and most likely the problem that burnt up the computer in the first place...

The ECV runs on 12 volts and the circuit for the lights that go into the ECU to dim the display is 24 volts! I cut out the dimmer circuit, and...
Luckly, I was quick enough and didn't smoke the ECU!

OH MAN! What a workout!

RE: Libelula Lives!!!

June 15th, 2008.

Dear Joaquin Suave:

and a hat's off for your persistence.....! I think that I'll stick to the stone age technoloy of the M35A2.... there's a lot more parts around, and little, if any electronics (beyond the TACOM switch-None!), and most repairs can be jury rigged to get you out of a hole....
It is quite cool, that you have taken one of the prototype FMTV's to restore, but like all things prototypical, usually the spare parts aren't to be found and are lordly expensive. I find you cutting the gasket to be most informative, I guess I would have done it on a steel workbench, drawn it with pen and ink, and cut it with a razor...... different technologies for different generations......! I have found often that the computerized machinery of today is more time consuming in doing a one-off then the traditional methods, but the old ways takes much more skill to operate, the new ways process or batch run them faster....

Keep up the good work!!!
Sincerely,


Kyle F. McGrogan


1971 Kaiser Jeep M35A2 Wo/W "Saddam's Nightmare" Desert Storm and Vietnam War veteran truck
1968 Johnson Corp M105A2 1-1/2 Ton Two Wheeled Cargo Trailer
1967 Hercules Gas Gen-Set APU MEP023A
1963 Swiss Army Cargo Unimog, S.404.114 MB

Also a driving me crazy problem

hey guys nice to meet you all my name is Gary I live in Western Australia
I also have a problem with my truck same as the one on this tread but a 6x6
The problem I have is the gear control/transfer out of the dash
was removed before I purchased the truck I was told it was sent to America for repairs but got lost in transit so now i have no controler at all ... So What can i do ????
here is the model number and part number
Model MD-D7
Part Number 29500226
And this stage I am very close to removing the box and putting in a mechanical Allison and adapting the transfer if that’s at all possible ..
I’m not sure yet as I have to pull it down to see if it can be done

[FONT=&quot]TACTICAL TRUCK CORPORATION[/FONT] CONTRACT NO.DAAEO7-89-C-R002


thank you guys very much in advance if you can help me on this

this too is driving me crazy

Gary

Contact Joel Gort at Weller Truck Parts in Grand Rapids, MI. Allison Department. Give him the 10 digit vin off the Allison and tell him what is going on. He has done this for 30 years and is very familiar with the military applications. His Direct line is 616-724-3744. He will help you with any wiring issues and give you information such as wiring diagrams, ohm readings, etc.

you know that's a 6 year old post