Driving with front drive shaft Disconnected

[motorhead87]

Probably been discussed but I can't find it - link it up if you have relevant threads.

Would it be possible to drive an LMTV without a front driveshaft? Could something like a quick disconnect be used to choose when it's engaged and not? https://www.remcodsc.com/

The Tcase would still be trying to spin the front driveshaft but there should be less driveline loss. Though only what, 70 or 50% would be reaching the rear wheels, so maybe this would be worse.

Thoughts?

 

[ramdough]

I believe in mode it would work, but then your speed would be limited and if you have a 6x6, your rears would be tied together.

I would not do it umm m less it is just to reposition it for working on it.


Sent from my iPhone using Tapatalk

 

[motorhead87]

I believe in mode it would work, but then your speed would be limited and if you have a 6x6, your rears would be tied together.

I would not do it umm m less it is just to reposition it for working on it.


Sent from my iPhone using Tapatalk

Why would speed be limited?

 

[jwchameleoncorp]

Are you disconnecting it for towing purposes? Recently I had an experience at work. I'm a fireman and we had to get our tiller truck towed. Watching the heavy tow operator was a great learning experience. He DID have to disconnect the drive shaft on the fire truck to tow it. That's when I showed him a picture of my 1083 6X6 and asked how he would tow it. Without hesitation he said you don't have to remove any drive shafts on the FMTVs as long as all tires are free to spin. He said he does it all the time with these rigs.

So if you don't have a flat bed tow truck, pick the FMTV up by the axel but DO NOT secure the tires. They all should be able to spin freely. You can tow it this way for thousands of miles with zero harm to the truck's drive line.

Sent from my SM-N975U1 using Tapatalk

 

[wheelspinner]

Probably been discussed but I can't find it - link it up if you have relevant threads.

Would it be possible to drive an LMTV without a front driveshaft? Could something like a quick disconnect be used to choose when it's engaged and not? https://www.remcodsc.com/

The Tcase would still be trying to spin the front driveshaft but there should be less driveline loss. Though only what, 70 or 50% would be reaching the rear wheels, so maybe this would be worse.

Thoughts?

Short answer is no. The transfer case is basically an open differential until you press “mode” which hard locks the power distribution 50/50 front to rear. The reason it won’t move with the front drive “disconnected “ or removed without putting the trans in “mode”. The drawback is putting it in mode limits the trans to 1-5 gears and locks out 6/7. This is the reason you will be speed limited.

 

[motorhead87]

The 'problem' I was trying to solve was how to let the truck easily transition from 4x4 to 4x2. Improved mpg/noise/wear n tear.

That is one hell of a wrecker to tow a ladder truck!

 

[motorhead87]

Short answer is no. The transfer case is basically an open differential until you press “mode” which hard locks the power distribution 50/50 front to rear. The reason it won’t move with the front drive “disconnected “ or removed without putting the trans in “mode”. The drawback is putting it in mode limits the trans to 1-5 gears and locks out 6/7. This is the reason you will be speed limited.

Ah ha - Answers that one plain and simple.

 

[jwchameleoncorp]

The 'problem' I was trying to solve was how to let the truck easily transition from 4x4 to 4x2. Improved mpg/noise/wear n tear.

That is one hell of a wrecker to tow a ladder truck!

Haha! It was HUGE! I had to tiller the back of the fire truck while he towed it. Felt like it took 30 seconds to clear intersections!

Sent from my SM-N975U1 using Tapatalk

 

[ramdough]

The 'problem' I was trying to solve was how to let the truck easily transition from 4x4 to 4x2. Improved mpg/noise/wear n tear.

That is one hell of a wrecker to tow a ladder truck!

I think the cheapest and easiest way to get better fuel economy is to buy a different vehicle. You could maybe get a little with higher tire pressure, high speed gears, take weight off where you can..... but ultimately you will probably only save a little. You are not going from 4x4 to 4x2. You are going from AWD to no wheel drive unless you swap your transfer case with a different type and then add locking hubs (which aren’t made for these trucks)..... just to save very little.

I would look for a Unimog if you want selectable with better mileage. They get almost double, but your box must shrink a little.


Sent from my iPhone using Tapatalk