2nd Gen Non-Engine/Transmission 4x4 vs 4x2 rear axle

[AutoRepair]

Does any one know if the 4x4 and 4x2 axles interchange? I notice they are listed as different on ebay, but I can't imagine why. They look the same, all the measurements look the same. I figured dodge just threw blocks on top of the 4x4 units. (my dana 70 just spun all the carrier shims out on both sides... I'm not so sure I want to re-shim it only to have the carrier bearings spin again. ) Thanks in advance for any info.

 

[NIsaacs]

Like you, I can't think of anything that might be different, possibly the wheel flange to flange width?



The D-70 is famous for a loose carrier bearing surface, usually just the left side. It will require a new/different carrier.



Nick

 

[Cosmo]

The only thing I can see that might be different would be the pinion angle. Higher for 4x4 of course.

 

[jgillott]

I was aware of a width difference between the single and dual rear wheel applications, but didn't think that there was one between 2x4 and 4x4. Could be wrong however.

 

[AutoRepair]

10-4 on the loose carriers. This is the second one I have seen. It's got me contemplating the D80 swap, not that I need the extra strenght, I just don't want to do this again. If I end up getting a 4x2 axle, I'll post notes of what it takes to make it fit. Thanks for the replies guys.

 

[HHhuntitall]

Should drop right in... I put a D70 wrecked 2x4 in a rebuilder I bought awhile back. The original 70 was pretty iffy, sounded like a cat had his tail in the diff, but I couldn't find any hair, just metal shavings... . I opted to pull it and slap the other one in to get it sold. I didn't see any difference on either one, 2 to 4x4. I put one in my '95 gasser 1/2 ton, too. I had to fab some spring pads and spring spacers, but it had 2. 5" springs... ... . If you go with the heavier axle, you'll probably have a larger U-joint yoke in it than in yours... . I don't think they'll swap... . so you may have to redo your driveshaft or find a different yoke... . I could be wrong... . but that should be the only difference.

 

[AutoRepair]

great info thx! The u-joints should b the same, both are cummins trucks. Thx again guys!

 

[Cosmo]

Even if the joints are different, you can get a combo joint with two different sized caps.

 

[Vaughn MacKenzie]

The main thing I know of dimensionally isn't between 4x4 and 4x2 but between model years. . . 2000 and up axles should be 2" wider since Dodge increased the track width 2" that year.

 

[HBarlow]

That's a very good point I would have completely overlooked. I believe thet widened track was to accomodate the new larger LT235/85R16 wheels and tires.

 

[Cosmo]

autos. msn.com doesn't seem to think that the track changed, it shows 68" rear track for both 98 and 02.

Heck, even 03 is only . 2" wider.

 

[HHhuntitall]

That's a very good point I would have completely overlooked. I believe thet widened track was to accomodate the new larger LT235/85R16 wheels and tires.

Exactly. They didn't change the wheel center line or spring width, they just gave each wheel 1/2" more backspace, which moved the overall rim outside width out 1", plus the width of the larger tire bulge, so @ 2". This gave 1" more space between the duals to accomodate a taller sidewall.

 

[Vaughn MacKenzie]

autos. msn.com doesn't seem to think that the track changed, it shows 68" rear track for both 98 and 02.



Heck, even 03 is only . 2" wider.

I had the back ends of my '01 2wd and '98 2wd on jackstands with the tires off at the same time and did some measuring, between axle flanges the '01 was exactly 2" wider than the '98. 4x4s would likely be the same.

 

[NIsaacs]

autos. msn.com doesn't seem to think that the track changed, it shows 68" rear track for both 98 and 02.



Heck, even 03 is only . 2" wider.

They are probably using tire center line for track width. When the axles went wider, the wheel back space changed to keep the same center line.



I tried to put a set of 17" tires and wheels off an '06 on my '91 and they looked funky, inset too far.



Nick

 

[Cosmo]

Your 06 has AAM axles, which would make sense about them being different widths than the Dana axles.

 

[NIsaacs]

Your 06 has AAM axles, which would make sense about them being different widths than the Dana axles.

That makes sense, I didn't think about that. However the '06 tires and wheels are fine on my '01 but not the '91. So somewhere between '91 and '01 something changed. One time I tried to put my '01 spare on one of my trailers and it hit the spring, not enough backspace.



Nick

 

[JMcCoy]

I have done a lot of research on this since I am swapping in a 2002 D80 disk brake rear for my drum D70. The only difference I have been able to figure between the 2x4/4x4 rears is the differential cover. The 4x4 cover is larger to accomidate more fluid.

 

[AutoRepair]

Well, the axle is in the truck. Looks like the major differences are: the passenger E-brake cable is shorter on the 2wd, and the shock mounts work, but locate the shocks about an inch lower on the axle than the 4wd. I checked pinion angle on the old axle and will compare it to the new one, but I imagine any angle difference will be made with the lift bocks... just a guess, we'll see. Thanks again for the info!