4WD question
- Thread starter booger
- Start date
dieseltrooper
Inactive
Weird!
Never heard of one like that. What year/model is it? I had a jeep like that once, but it was after breaking a rear u-joint and had to drive home with the front driveshaft only...
He's in there snoring right now but I'll ask him in the morning. His current (well, he got a "new" S10, so he's not driving it right now) truck keeps throwing U-joints everytime he drives it. I think he has them about all replaced now. 
If it's a decent truck, he's gonna trade his POS truck for a van and the aforementioned funky 4WD truck, both running.
If it's a decent truck, he's gonna trade his POS truck for a van and the aforementioned funky 4WD truck, both running.
Hamilton Felix
Inactive
My first reaction to booger's post was WHAT?!?!! But Dredge just tickled my brain. A full time 4WD that's not in Lock, has a center differential. If you stomp it, either end can spin, leaving the end with best traction sitting still. Could it be that's where the "front drive" story comes from?
The only 2WD/4WD rigs that come to mind with 2WD being front drive, are small foreign cars like my 1987 Subaru wagon.
Dad broke a rear axle on my 1956 International 4x4, so he dropped the rear driveline and put the transfer case in Lock, kept driving on the front axle. I've run my 1966 International the same way, when I had a bad rear U-joint. I even drove our 1996 3/4 ton Suburban to the dealership on front power, having pulled the rear live axles because the rear diff was running hot due to bad pinion bearing.
But you have good advice in this thread. In general, the front drive parts are lighter on a 4x4 pickup, because they are not expected to be used constantly.
The only 2WD/4WD rigs that come to mind with 2WD being front drive, are small foreign cars like my 1987 Subaru wagon.
Dad broke a rear axle on my 1956 International 4x4, so he dropped the rear driveline and put the transfer case in Lock, kept driving on the front axle. I've run my 1966 International the same way, when I had a bad rear U-joint. I even drove our 1996 3/4 ton Suburban to the dealership on front power, having pulled the rear live axles because the rear diff was running hot due to bad pinion bearing.
But you have good advice in this thread. In general, the front drive parts are lighter on a 4x4 pickup, because they are not expected to be used constantly.
Okay, here's what he says, no chick translation this time. 
"78dodge 1/2 ton full time 4wheel drive but when you shift the 4wheel drive shifter it has 2 wheel and its the front wheels"
The fella has three of them and they're not broken.
He's considering getting one of them and just wants to know if it'll be a good truck or if that setup isn't common because it sucks and he should avoid it. Thanks!
"78dodge 1/2 ton full time 4wheel drive but when you shift the 4wheel drive shifter it has 2 wheel and its the front wheels"
The fella has three of them and they're not broken.
He's considering getting one of them and just wants to know if it'll be a good truck or if that setup isn't common because it sucks and he should avoid it. Thanks!
I gotta say that's an absolutely new one to me.
I've got a 77 M880 Dodge here - full time FWD, basically just does the low lock thing when you shift the xfer case.
You've got a W150 - or at least that's what it should be. It might have the 318 or 360 in it, and it probably has the 727 tranny. It also probably has the NP203 xfer case in it - a chain driven full time 4wd case also used on GMC and Chevy during that period. Unless it's been somehow kitted, that case will drive both ends of the truck at all times. With a conversion kit you can free wheel the front hubs, but it'll still be turning the front driveshaft. There was another conversion kit for the xfer itself, that would make it a part time 4wd case, but it was expensive and most people didn't really like the chain drive aspect of the NP203, so they just put a heavier case in.
As Dredge said, that front end isn't meant to be used as a full time front wheel drive - something will go eventually.
The other thing about Dodges from this era is they had really lousy U-Joints - you have to keep on top of them. Make sure they're lubed and in good condition. Carry a spare or two. Don't ask me how I know
Anywhoo....with a full time 4x4 system, both ends drive at the same time, but there's a differential action going on - power will go to the end that has the least traction. If same traction or resistance it is equally split. Once you drop it into low lock or high lock, the power transmission is equalized no matter what...so you can take out a driveshaft and still drive on the other axle. Why's this important? Lots of people do this, since it's the cheap way to get 2 wheel drive and better fuel economy, but the problem is that it wears out the xfer case pretty fast and sooner than later it's time for repairs.
I suspect what happened was someone jacked up the front of the truck, put it in gear, started her up, and saw the front end was turning and assumed it was front wheel drive, since the rear wasn't moving.
Czechsix
I've got a 77 M880 Dodge here - full time FWD, basically just does the low lock thing when you shift the xfer case.
You've got a W150 - or at least that's what it should be. It might have the 318 or 360 in it, and it probably has the 727 tranny. It also probably has the NP203 xfer case in it - a chain driven full time 4wd case also used on GMC and Chevy during that period. Unless it's been somehow kitted, that case will drive both ends of the truck at all times. With a conversion kit you can free wheel the front hubs, but it'll still be turning the front driveshaft. There was another conversion kit for the xfer itself, that would make it a part time 4wd case, but it was expensive and most people didn't really like the chain drive aspect of the NP203, so they just put a heavier case in.
As Dredge said, that front end isn't meant to be used as a full time front wheel drive - something will go eventually.
The other thing about Dodges from this era is they had really lousy U-Joints - you have to keep on top of them. Make sure they're lubed and in good condition. Carry a spare or two. Don't ask me how I know
Anywhoo....with a full time 4x4 system, both ends drive at the same time, but there's a differential action going on - power will go to the end that has the least traction. If same traction or resistance it is equally split. Once you drop it into low lock or high lock, the power transmission is equalized no matter what...so you can take out a driveshaft and still drive on the other axle. Why's this important? Lots of people do this, since it's the cheap way to get 2 wheel drive and better fuel economy, but the problem is that it wears out the xfer case pretty fast and sooner than later it's time for repairs.
I suspect what happened was someone jacked up the front of the truck, put it in gear, started her up, and saw the front end was turning and assumed it was front wheel drive, since the rear wasn't moving.
Czechsix
Hamilton Felix
Inactive
Czechsix is making sense. My work car used to be a '79 Jimmy with NP203 and full time four wheel drive. There is no true two wheel drive in these vehicles. When you get into bad going and pull the lever, you lock a center differential in that transfer case, forcing front and rear drivelines to turn the same speed. Until you lock it, you can have one end turning and the other end sitting still, if traction is different. With one wheel on ice and the other three having good traction, you can even have ONE wheel spinning while the other three sit still (assuming you have an open differential in that drive axle).
Since a large municipal utility was buying gas and tires and doing the maintenance, I was happy with the rig. If if had been my own, I'd have been less happy with the poor mileage and rapid tire wear (rotate frequently). But heck, most full size trucks get lousy mileage, and it's a fairly simple system to operate.
My full time Jimmy was replaced by a 1987 Jimmy with part time four wheel drive and automatic hubs. I recall that the full time rig with the NP203 had a big rugged cast iron transfer case. The '87 had a fragile looking aluminum transer case; I had the shop put a skid plate on it.
I never had trouble with the automatic hubs on the '87 Jimmy, but the 1995 Ford Bronco that replaced it had lousy automatic hubs. We bought three, and two lost their hubs within a couple of years. I am happy with the Warn heavy duty hubs I have now.
For a work truck, not a commuter, I don't see anything wrong with a reasonably healthy '78 Dodge full time 4x4 rig.
Since a large municipal utility was buying gas and tires and doing the maintenance, I was happy with the rig. If if had been my own, I'd have been less happy with the poor mileage and rapid tire wear (rotate frequently). But heck, most full size trucks get lousy mileage, and it's a fairly simple system to operate.
My full time Jimmy was replaced by a 1987 Jimmy with part time four wheel drive and automatic hubs. I recall that the full time rig with the NP203 had a big rugged cast iron transfer case. The '87 had a fragile looking aluminum transer case; I had the shop put a skid plate on it.
I never had trouble with the automatic hubs on the '87 Jimmy, but the 1995 Ford Bronco that replaced it had lousy automatic hubs. We bought three, and two lost their hubs within a couple of years. I am happy with the Warn heavy duty hubs I have now.
For a work truck, not a commuter, I don't see anything wrong with a reasonably healthy '78 Dodge full time 4x4 rig.
Thanks for all of the info, fellas.
He's decided against it. Turns out his boss has a truck he'd rather have and thinks he can talk him into selling. Something about a 4-bazillion motor, some supermanish tranny, and diamond-studded titanium something or other. (Sorry, more chick talk. )
He's decided against it. Turns out his boss has a truck he'd rather have and thinks he can talk him into selling. Something about a 4-bazillion motor, some supermanish tranny, and diamond-studded titanium something or other. (Sorry, more chick talk.
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