Easiest part time swap for early eagles??

[amcsedan]

I keep passing over 80 Eagles as a daily driver because I would prefer part time 4wd.

Saw threads on 229 swaps, but would have to add vacuum lines or switches too, right ?

What is the best, or easiest or cheapest solution to changing a 1980 eagle to part time 4wd

[ammachine390]

do you mean part time or switchable full time?

[Whuntmore]

I'm going to assume you're pulling the guts out of another eagle... So I guess that depends on whether you want to be able to switch on the 'fly' or not.  

It's not just the transfer case, it's also based on the disconnect (or non-disconnect) front axle.

If yes, then you're not saving any fuel mileage there.  The front end is always locked.  You could switch over anything IIRC about '85 or newer - that's when they started 'shift on the fly'

If No, then you're looking for anything after mid-to late '81 (when they started having 2-4 wheel drive shifters), till about late '84 - Before 'shift on the fly'.  You can tell easily.  Look for cars with the pull down knob for shifting between 2 and 4 wheel drive.

Any of those before 'shift on the fly' will have disconnect front axles.  That will save you some fuel, but you'll also have to stop to shift.

[Mechanic]

To be honest, I'd leave it full time. My SX/4 is full time and the one tank of gas I did before everything went down hill I got somewhere is the high 20's for MPG's. And whuntmore is correct, your not going to be saving a whole lot on gas because you don't have the front axel disconnect.

But if you want a case to swap in, I would suggest doing a 242 swap out of a jeep and then just change your driveshafts, at least that way you don't have to worry about the bull crap vacuum system.

[Whuntmore]

Which is another good point, do you want some low range in the TC, or just keep it (sorta) stock? 

[amcsedan]

 Mileage is definitely a big part of it .... has to make a difference if guys with FSJ even go further with manual locking hubs right ? The drag of the driveline always being "on" ...

The other part of it would be wear and tear ; as a DD, wouldn't part time 4wd put less wear on the Tcase and front axle bits?

Vacuum would be avoided if possible, and it does not have to be guts from another Eagle.

Researching for my GW I was looking at NP 231 cases, but low range is not required.
I am on my way to being an AMC nutjob driving only AMC daily . Have my 86 GW and have sold both my Eagles
in the past 2 years.  Thought I wanted a Concord to avoid  having 2 vehicles with 4wd as it  seemed unnecessary.

But there are some nice Eagles around, and in fact , it's the silver 80 with the black interior listed here and elsewhere that was the final straw for me reconsidering a full time 4wd Eagle as an option .

Out of curiosity, what is the difference between part time and switchable full time ??

Can you put it something like a 208 or 228 , and does anyone make manual hubs for the Eagle
to avoid changing out the front axle ?

[Mechanic]

Alright, here is the 4X4 low down on the eagle.

Disappointingly, there is no easy way to unlock the "hubs" on an eagle that doesn't already have the front axel disconnect. The easiest way would be  to swap in another front diff out of an eagle that has it. Not a small job. The eagles with from axel disconnect work the same as pretty much all IFS trucks I've seen, including dodge, ford, GM, and toyota. They all just engage the middle part of the diff. So no matter what you do, the half shafts will always be turning. Front axel disconnect, no disconnect, full time, doesn't matter, those will always be turning.

(oh, the difference between stop and shift, shift on the fly, and full-time, is, for the first both a disengagable front axel and T-case, for the second just a desengagable t-case, and for the last, none of those things.)

Having no front axel disconnect seems to affect your millage by 1-2 MPG from what everyone else says, I've personally never calculated it.

Having a transfer case disengage would help a little bit, but not overly, and because you wouldn't have a front axel disconnect, your front driveshaft would be spinning all the time. So wear and tear would also not be improved either.

Long and the short of it. If you've got an 80 and you want to swap cases for fuel economy, it's more of a hassle then it's worth.

[Whuntmore]

Not much you can do here.  You can either get a concord/spirit/etc.  or do a good stroker motor, and have the rest of drivetrain rebuilt with HD parts (or some upgrades).  That will give you better mileage.

[Jurjen]

If you have an 80 model, please leave it as it is.
It is the way the designer intended the car to be.
It is a trouble free system and changing it doesn't bring you much.
Personally I think the early models are the most desirable too.

[Mechanic]

If you have an 80 model, please leave it as it is.
It is the way the designer intended the car to be.
It is a trouble free system and changing it doesn't bring you much.
Personally I think the early models are the most desirable too.

I second that, my favorite years are 80-82

[amcsedan]

 Thank you all

Likely a case of overthinking it , huh ?

It's such an old system that I assumed there must be a "better" way .

I would intend on "upgrades" like TFI ( or is it MIU now?) , I have an Offy intake on hand already , as well as a 390 cfm Holley ......  I assume those would be good for 2-5 mpg..... and losing a mile of hoses ....

Even my wife's 04 blazer binds on turns in 4wd, so I was worrying about full time awd on city streets some too .

[jim]

If you have an 80 model, please leave it as it is.
It is the way the designer intended the car to be.
It is a trouble free system and changing it doesn't bring you much.
Personally I think the early models are the most desirable too.

Me, too.

[Mechanic]

Thank you all

Likely a case of overthinking it , huh ?

It's such an old system that I assumed there must be a "better" way .

I would intend on "upgrades" like TFI ( or is it MIU now?) , I have an Offy intake on hand already , as well as a 390 cfm Holley ......  I assume those would be good for 2-5 mpg..... and losing a mile of hoses ....

Even my wife's 04 blazer binds on turns in 4wd, so I was worrying about full time awd on city streets some too .

Nope, she turns as smooth as can be. Even if your at 100% lock you barely have a hint that it's fighting.

[Whuntmore]

If you have an 80 model, please leave it as it is.
It is the way the designer intended the car to be.
It is a trouble free system and changing it doesn't bring you much.
Personally I think the early models are the most desirable too.

I also agree with what Jerjen says here.  the 1980's early '81's are the most trouble free drive train.  That's what it was meant to do.  And I've driven Pat's early SX/4.  You can cut the steering all the way over left or right, and she's smooth. 

Some people are determined to do swaps, and several members will try to talk them out of it, but it's usually to no avail.  (no offence, but I've given up in trying to do that anymore.)

But the car is really good the way it is.  Do an EFI swap, the better carb, get rid of the 'spare' hoses, but unless you're turning it into a bogger, or rockclimber, don't bother swapping the drivetrain.  tune it up like crazy, and you could be getting high 20's in mileage.

[ammachine390]

Even my wife's 04 blazer binds on turns in 4wd, so I was worrying about full time awd on city streets some too .

ALL Eagles are full time four wheel drive. The early models were just permanently in full time 4 wheel drive and the later models can be put in 2 wheel drive as well.  Full time means it can be used anywhere, not just off road. It's part time systems (which can only be used on loose surfaces) that bind when they are driven on pavement in 4 wheel drive.

The later Eagles have a very unique system. Most FULL Time 4 wheel drive systems cannot be put in 2 wheel drive, since they can be driven on dry pavement in 4 wheel drive (like the 80 eagle or suburus AWD). And all part time systems must have a 2 wheel drive because they cannot be driven on dry pavement in 4x4.  AMC gave you the choice (on later Eagles) of 4x4 you can use ALL the time with the option of 2 wheel drive when you want better mileage