Third From Texas
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Interesting to know that Motorola also made ECUs for LMTV/MTVs.
I'd only seen Dana Spicer ECUs until today.
I'd only seen Dana Spicer ECUs until today.
Steel Soldiers now has a few new forums, read more about it at: New Munitions Forums!
I did all the job... Interiour of cab and habitat, external painting of whole truck etc...whomever did the interior of both cab and rear habitat did an awesome job. Would love to see more. Curious of your rear bumper too.
Looks like about the same size box as I'm going with (a 14' ambulance box like Coachgeo is using as well). His truck already has the spare and intake removed, but I plan on leaving it like you did then add a slight cut in the rear to maintain the departure angle.I did all the job... Interiour of cab and habitat, external painting of whole truck etc...
Maybe the 90psi valves have harder springs, and the M1078 have only 70 psi wheel valves? For sure you know more than me, so excuse me if I insist in this 70/90 psi diffrence...On the m939a2 trucks there was an upgrade for running higher pressure. It was a newer ecu, replacement pressure sensor and wheel valve upgrades to what appears to be the same ones as the lmtv uses. Is there any way to trick the first gen lmtv systems into running higher pressure by just changing the pressure sender? Or putting a small resistor inline with one of the sensor wires so the system thinks the pressure is slightly lower than it really is.
The sensor is a atmospheric or PSIA so normal atmosphere it puts out roughly .573 volts at .039psi/volt. Say 80psi = 3.12v. If you put in a "Resistor Divider" designed to reduce the signal wire voltage by 10% the system will see 80psi tires as 72psi and what it thinks is now 80psi tires would actually be 88psi (roughly). Keep in mind that atmospheric reading is now 10% low and if you live on a mountain the lower reading could cause a Fault. The more important issue is that the wheel valve on the LMTV front left can't close much above 84psi on a warm day. Resistor Divider = 3 resistors configured properly across the signal and ground wires.
Why is the front left different than the other valves? I was thinking I would only have to put a resistor on the positive side not the ground.
The front QRV is mounted on the right side frame rail so there is allot longer tubing to get to the left hub. That extra tubing make it harder for the valve to close at higher tire pressures and it get's worse as the valve diaphragms get's colder. Messing with the transducer supply current may cause problems that's why it should be on the signal wire which is very high resistance. I am not advocating trying this.
My 94 has Motorola symbol on circuit board.Interesting to know that Motorola also made ECUs for LMTV/MTVs.
I'd only seen Dana Spicer ECUs until today.
Neither of those are for an FMTV. Both are for M939's and far as I know where not used on any fmtv's. IF either are on your truck then someone frankensteined the ctis. Probably not the case. Did you buy from individual or from Military auction?Hello all.
Today I dig a little bit more. Seems that there are 2 diffrent valves for 2 diffrent pressures:...
I'm proud to be member of this fantastic forum, much better than other forums where the netiquette don't exist...Neither of those are for an FMTV. Both are for M939's and far as I know where not used on any fmtv's. IF either are on your truck then someone frankensteined the ctis. Probably not the case. Did you buy from individual or from Military auction?
BTW..... great to have an FMTV owner from other side of the Ocean participating.
Interesting indeed. I did a unwanted chalk test some days ago, with 90psi. This pressure is definitivly too high, The tires have only in the middle (60-70%) ground contact. 60 psi looks more natural..Some good reading applies here about what is, isnt good air pressure. Do some additional searches about max psi. Some of it surprised me. Just maybe the German feller who modified things is a pretty smart feller?
https://www.4wheelparts.com/a/tire-wheel-package-guide-tire-pressure-checker
but was the setup he put in intended not for now but for AFTER camper box installed? IMHO if all your valves etc. check out as no leaks.... leave it as is and re-evaluate after your camper box is installed and fully loaded. Unless of course your driving her a bunch right now and do not want to wear out your tires.Interesting indeed. I did a unwanted chalk test some days ago, with 90psi. This pressure is definitivly too high, The tires have only in the middle (60-70%) ground contact. 60 psi looks more natural..
Christian
No, he change the ECU because the old one did not work. He put the only one that is working, and that is the M939 wrecker ECU...but was the setup he put in intended not for now but for AFTER camper box installed? IMHO if all your valves etc. check out as no leaks.... leave it as is and re-evaluate after your camper box is installed and fully loaded. Unless of course your driving her a bunch right now and do not want to wear out your tires.
whomever did the interior of both cab and rear habitat did an awesome job. Would love to see more. Curious of your rear bumper too.
As to MTV CTIS valve causing issues with other components..... have not heard/seen a mention that valves used are any different between the LMTV's and the MTV's. Pretty sure it is all same valves so once you're all repaired in leaks and valves, if it is an MTV controller you should be fine in that respect.
Others with more knowledge will chime and and clarify though.
Looks like about the same size box as I'm going with (a 14' ambulance box like Coachgeo is using as well). His truck already has the spare and intake removed, but I plan on leaving it like you did then add a slight cut in the rear to maintain the departure angle.
Love what you did for the console and headliner. Top-notch work there !
Any more pics from the box interior? What is on the forward side of the room?
And as Coach said, show some more of that bumper and how it hinges up.
I may have missed it in the thread somewhere but could the issue be that the box from the 939 is not compatible with the LMTV CTIS system?No, he change the ECU because the old one did not work. He put the only one that is working, and that is the M939 wrecker ECU...
Christian
Thanks..... next time you swing it up please take a shot of how it clips/pins?? up out of the waySorry for the delay, but I was taken by the ctis project. Here is a picture of the back bumper....[img .... /img]
Christian
Yes its not compatable.... from previous postings.... not heard back on where he is on his ctis adventure. Being in Italy he can't just find another known to work one to swap test with that easily.I may have missed it in the thread somewhere but could the issue be that the box from the 939 is not compatible with the LMTV CTIS system?
Should you try to get a known good LMTV box and instal it to see how it acts?
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