New guy looking for answers

[Hotrod1340]

Hello All, I could use some answers, I have done some searching but i think it would be easier to just ask .

I just bought a 1977 M887 all the standard stuff: 318, dana 60 & 40, torqueflite,,,,,

My goal for this truck is weekend toy, run to the dump plow some snow..goof around. its in fairly good shape and got it for what i thought was a good price.

He gave me a power steering, steering box, i just need to find a pump. but one problem it had or has is a broken front drive shaft ( not the U joint) he explained it was a weak spot with these trucks and a new one would cost about 175 bucks?

Now Here is were it might get ugly.. He was driving the truck in 4 hi loc, (no front drive shaft) i ask him why and he mentioned he was told to drive it that way because of the missing front shaft (It dosent sound right to me either), so during my test drive i put it in 4 lo and lo loc, everything worked the way it should (gearing wise) I pulled it back in 4 hi lock and drove back. when i got home I tried to put it in 4 hi (not loc) and it wont move in drive only reverse, So my question is this. could this be a linkage problem or a transfer cas problem?

After we figure this out you can show me where the thread is to (get the power steering installed) and find me a plow and we will be good.....

Thank in advance for your help.... Here is the add for the truck...SEE BELOW

5/4 Ton, 318 V8, Torqueflite 727 automatic transmission, New Process 2-speed transfer case, NP203 (full-time 4x4) - Leaf springs all around - Dana 44 solid front axle (1:4.09 gearing) - Dana 60 solid rear axle (full-floating, 1:409 gearing), Power Disc Brakes.
38,xxx actual miles. Ex U.S. Army. 36x12.5 Goodyear
Humvee Tires and Floor Mat with sound deadening.
Runs & drives great! This truck cruises comfortably at 70 mph.
Missing front drive shaft. Willing to install new drive shaft for additional $200.
Small Crinkle in drivers side front fender.

 

[Crash_AF]

The 880 series has a full time transfer case. That means that there is a differential in the transfer case which divides power between the front and rear axles without binding. What this means is that if the front driveshaft is gone, the power will go to the front output shaft (the path of least resistance) and send nothing to the rear. Very similar to an open differential in a truck sending power to the wheel in the mud while the wheel on the pavement just sits there leaving you stuck.

Hi Lock locks the differential in the transfer case and forces the power to both outputs, allowing the rear to turn.

It won't hurt anything to drive it around in high lock without a front driveshaft since there is nothing to bind up.

Later,
Joe

 

[Hotrod1340]

Thanks joe i feel much better about the transfer case issue.....

we still need the power steering thread... and could someone explain the differant transfer cases? 203, 205,,,, i thought they were almost all the same..

is the dana 60 and the 40 a posi unit?

 

[StrykerPez]

So with this transfer case, you could drive around in 4hi on the streets with no prob?

 

[M725]

So with this transfer case, you could drive around in 4hi on the streets with no prob?

There is no 2 wheel drive in a M880, It is full-time 4x4 drive.

 

[M725]

My 1974 Chev Blazer came wth the same set-up from the Factory. It was a big thing in the early 70's.

 

[Bob H]

New front drive shafts @ colemans surplus $99.00

front & rear axles are both open differentials. D44F 4.09 & D60 rear 4.10 gearing.

get a PS pump from any 70's Dodge pickup, the pump mounts drivers side low.
I have a PS pump that mounts top center , to sell. required if truck has 24v system generator or a hydralic plow pump monted where the std PS pump would go.

Sounds like an Alfaheaven truck.

Those 36" Humvee tires mounted on skinney rims are just plain dangerous on ice! (amazing in mud though)

All service parts can be obtained at a parts store, tell them it is a W200 w/3500lb front axle.
water pump & radiator are same as W200 with air conditioning

 

[Hotrod1340]

Thanks for all the info....You are have been very helpfull...

Bob, should i be looking at the top mounted pump since I plan on putting a plow on it? And when you say (open differentials) do you mean Limited slip/PEG leg?

 

[Hotrod1340]

Cant that front drive shaft be repaired?

 

[Recovry4x4]

It can be repaired but not for $99 unless it just needs a joint.

 

[Hotrod1340]

Bob it does sound like a Alfaheaven truck. after checking the web site. I think it had a few owners from there to me.
The drive shaft has been ordered!

Does anyone have a picture of the powersteering pump installed?

Thanks again

 

[Crash_AF]

Thanks joe i feel much better about the transfer case issue.....

we still need the power steering thread... and could someone explain the differant transfer cases? 203, 205,,,, i thought they were almost all the same..

is the dana 60 and the 40 a posi unit?

The NP203 is a big heavy chain driven transfer case that is full time 4wd (Think the same as a HMMWV) that has no 2wd mode. Both axles are driven all the time with a differential in the middle to prevent driveline bindup. This is why there are no hubs to lock and unlock in the front.

The NP205 is a big heavy gear driven transfer case that is part time 4wd. It is very durable and is one of the strongest transfer cases ever offered in light duty (1T and under) trucks. The only shortfall in the transfer case is that it only has a 2:1 low range ratio compared to most modern transfer cases having a 2.72:1 low range. This does have a 2WD position and therefore the front axle has hubs that lock and unlock.

Both transfer cases were used throughout the 70's by the big 3 until they were replaced by the lighter (both weight and duty) aluminum transfer cases such as the NP208.

The front axle in the M880 is a Dana 44F. As far as I know, they were only offered with an open (non limited slip/locker) differential with 4.10 gearing.

The rear axle is a Dana 60FF with (again, as far as I know) an open differential and 4.10 gearing.

The base truck is a standard W200 with the heavier GVW package and heavy duty cooling system. Engine and transmission are standard 318 with TF727 3 Speed Auto.

Later,
Joe

 

[Elwenil]

It should also be noted that continuous driving with the NP203 in the Hi-Loc position and no front driveshaft will eventually wear out the lock in the differential and leave you stranded. Get the front shaft replaced ASAP and put it in regular Hi for on road driving. Also, a frequently mistaken point is the fluid in a NP203. Everyone wants to put 90W gear oil in it like most other cast iron cases but this is incorrect. The correct fluid for a NP203 is regular 10W30 motor oil.