Another Ahab
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Wow. Unbelievable!
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Steel Soldiers now has a few new forums, read more about it at: New Munitions Forums!
What have you done to your FMTV or LMTV today
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wandering neurons
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Update on the LMTV cab swap: the cab is bolted down properly. Back-of-cab hooks are adjusted but I’ve got work to do on the cab latch. Good news and bad news, good first: after a week of troubleshooting I got Goliath to start and run, only the fuel gauge inop so far, probably connector. Bad news: spent a week troubleshooting “failure to start” problem. Between the -20-1 and several contributors here, found the problem. Somewhere between pin 87 of relay K1 and TL33 on the Aux Starter Relay there is an open connection. Absolutely everything else tests good including oil pressure switch, trans control module and VIM, relays, circuit breakers, wires, grounds, etc. I need to check the back of the PDP and make sure that socket is ok but otherwise, I’m much happier. Long road to “complete” but this is the biggest and toughest hurdle.
Will start another post about the broken wire…
Am doing the Snoopy “Happy Dance”. Am tired too…
Thx all!
Will start another post about the broken wire…
Am doing the Snoopy “Happy Dance”. Am tired too…
Thx all!
wandering neurons
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Actually, in deciphering the electrical schematics, both the fuel quantity wire from the sender to the gauge as well as the below wire from K1 to the Aux Starter Relay run through P43 under the main dash panel. I'm going to start there and do continuity checks both directions from there. Stupid me, it may be unplugged from troubleshooting this problem initially. Would be just my luck.
More to come...
More to come...
Another Ahab
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A lesson from the Stoics of Ancient Rome:
- Laugh WITH the Gods, while they are laughing at you
Because there's plain nothing like a good laugh!
wandering neurons
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And a quote back to you along those lines:
Euripides: 'Those whom God wishes to destroy, he first makes mad.'
Which leads up to the fix for my starting/fuel quantity problem: P43 under the dash is the same shape as another Pxx (can't remember which) but more pins used. The other connector only uses 4 or 5 pins. Once I connected the right P to the right J, everything worked correctly! Starts correctly, fuel quantity reads correct, etc.
Similar problem with the fan solenoid under the PDP. The original cab on the truck was not original. Apparently, the original cab on my truck had been replaced with another LVAD cab according to a plate riveted to the dash. It must have come from a three-axle M1093 or 1094 as there is a dual air solenoid next to the CTIS manifold, whereas the normal M1078 and M1081 have a single air solenoid. The single solenoid is for the fan clutch. The dual air solenoid is for fan clutch and inter-axle air pressure.
That being said, I think that I had the fan clutch solenoid plugged into the inter-axle plug. Air didn't dump out of the solenoid as normal when the master power switch is turned off (the hiss under the dash when the air to the fan clutch is dumped at power-off).
So..... Getting closer. Finding leaks, and now can start buttoning up panels and rebuild the interior!
Euripides: 'Those whom God wishes to destroy, he first makes mad.'
Which leads up to the fix for my starting/fuel quantity problem: P43 under the dash is the same shape as another Pxx (can't remember which) but more pins used. The other connector only uses 4 or 5 pins. Once I connected the right P to the right J, everything worked correctly! Starts correctly, fuel quantity reads correct, etc.
Similar problem with the fan solenoid under the PDP. The original cab on the truck was not original. Apparently, the original cab on my truck had been replaced with another LVAD cab according to a plate riveted to the dash. It must have come from a three-axle M1093 or 1094 as there is a dual air solenoid next to the CTIS manifold, whereas the normal M1078 and M1081 have a single air solenoid. The single solenoid is for the fan clutch. The dual air solenoid is for fan clutch and inter-axle air pressure.
That being said, I think that I had the fan clutch solenoid plugged into the inter-axle plug. Air didn't dump out of the solenoid as normal when the master power switch is turned off (the hiss under the dash when the air to the fan clutch is dumped at power-off).
So..... Getting closer. Finding leaks, and now can start buttoning up panels and rebuild the interior!
Ronmar
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Well done!
wandering neurons
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This weekend I installed the Eco Hubs on my 1078. They sounded a little too good to be true, but Ronmar said they were worth it so I bought them. They are unbelievable. I have only driven about 30 minutes with them so far, but I cannot believe the difference. I pushed it up to about 65mph (as fast as I dared to go) and it was still in 6th gear. It would do 40 in 4th gear. I brought my wife for a drive and at 60mph I was able to talk to her in a normal voice. I coasted down a hill and it actually picked up speed. It is truly a different truck. It is, without a doubt, the best money I have spent on my truck to date.
MrGoldman
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I'm getting more convinced by the day I need these, How's the low-end power feel. I'm worried it will hurt my towing abilities.
I am afraid I don't know. Others who have done it say not much is lost, but I don't tow much.
Ronmar
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From a practical standpoint, It shouldn’t really effect your low end. With 2:1 at the hubs, you are not really using your torque converter, you ramp right up in 2nd gear and shift into 3rd. The TC not being really loaded is probably why 3rd gear hits so hard… With the 2:1 removed at the hubs, the TC will fill in as needed to replace the 2:1. You of course still have 1st gear available…
how much total weight are you talking about, vehicle + trailer?
how much total weight are you talking about, vehicle + trailer?
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Towing what? With which engine at what power?
Just put the 3.90's back into an Acela M1088 overland rig tipping the scales at 32,000 lbs. The owner is ecstatic with the results. Better in every metric. This is a 370 HP, 930 Ft/lb C7 truck.
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We don't tow much, though off road we lose traction first, and notice no loss in power. We love cruising at 60mph in 6th gear at 1,500rpm—
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3.90's?
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Right. Factory differentials with EcoHubs. I wish we had something more like 4.50's in, certainly wouldn't move to 3.07's with EcoHubs—
Ronmar
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yea, 4.5-4.7 diffs would be outstanding, they would be nearly twice the size, but the gearing would be fantastic for our 7 speed
If you are towing, all the added weight is NOT really enhancing traction. My little 3116 should pull 20K up a 41 degree slope in 1st. if I add a 20K trailer to that, the angle drops to 19 degrees, which is still pretty significant, but with or without 2:1 at the hub I am pretty sure i will be spinning wheels before i run out of torque, especially offroad...
If you are towing, all the added weight is NOT really enhancing traction. My little 3116 should pull 20K up a 41 degree slope in 1st. if I add a 20K trailer to that, the angle drops to 19 degrees, which is still pretty significant, but with or without 2:1 at the hub I am pretty sure i will be spinning wheels before i run out of torque, especially offroad...