Rear axle swap?

[Dave7.3]

Hey guys,
In the interest to get some taller gears, I've tossed around the idea of swapping my rear gears for some 3.55's compared to the 4.10s I currently have. Most of the consensus told me that it would cost more to swap gears (around $600) than just swapping rear axles.

In light of that idea, I have a line on a 1997 F250 PSD that is being parted out. The guy is gonna check the sticker for me, but if it has 3.55s will it swap in? The truck is an extended cab just like mine if that helps. Only difference is the truck is obviously newer but was an automatic compared to my manual.

Also, what work/additional parts would be required for a swap like this? I know it doesn't take too much, but the year gap could hold something I'm missing.

EDIT: I have factory Limited Slip, am I gonna kick myself later if this axle isn't?

 

[tjsea]

we just put a rear out of an 89 into a 97 and the only problem we hit was the u joint. The 97 had bigger caps than the 89. the yokes wouldn't swap for some reason I can't remember but neapco makes a conversion u joint with the two different size caps. I will see if I can get u the part number and the different cap sizes tomorrow.

 

[Goofyexponent]

Are you wanting to swap the WHOLE housing, or just the gears?

You can just unbolt the housing from your truck, and roll this one under it and secure it with new U bolts.....

.....OR.....

take the R/P out of teh parts axle and bolt it onto your ltd slip carrier and have it set up at a shop...then you would have a LTD slip 3.55

 

[Goofyexponent]

we just put a rear out of an 89 into a 97 and the only problem we hit was the u joint. The 97 had bigger caps than the 89. the yokes wouldn't swap for some reason I can't remember but neapco makes a conversion u joint with the two different size caps. I will see if I can get u the part number and the different cap sizes tomorrow.

I ran into this when rolling the 1990 rearend under my 1993.

HOWEVER, my yokes interchanged.

 

[Dave7.3]

Are you wanting to swap the WHOLE housing, or just the gears?

You can just unbolt the housing from your truck, and roll this one under it and secure it with new U bolts.....

.....OR.....

take the R/P out of teh parts axle and bolt it onto your ltd slip carrier and have it set up at a shop...then you would have a LTD slip 3.55

I was hoping to swap JUST the gears, but I was told it would require realigning the gears in a shop to do? That and it would be cheaper for an axle swap...now I'm not so sure...

 

[tjsea]

I don't remember what caused a problem with swapping the yokes. I do know it was easier to use the conversion u joint.

 

[u2slow]

I guess a limited-slip never 'did it' for me... I much prefer lockers.

In case you're thinking locker, you have the extra option of an inexpensive lockright, but only for the open diff.

 

[Dave7.3]

I guess a limited-slip never 'did it' for me... I much prefer lockers.

In case you're thinking locker, you have the extra option of an inexpensive lockright, but only for the open diff.

I've never had a truck with a locker before actually...the limited slip seemed pretty stout to me.

 

[Optikalillushun]

the yoke is different because the later 10.25s have a longer pinion.

the swap itself is as simple as it sounds. u can take the limited slip from ur old rear, blow off the ring gear bolts, transfer the tone ring and bam.

 

[Dave7.3]

the yoke is different because the later 10.25s have a longer pinion.

the swap itself is as simple as it sounds. u can take the limited slip from ur old rear, blow off the ring gear bolts, transfer the tone ring and bam.

I'm guessing the longer pinions were in the 92+ trucks along with the speedo being moved to the rearend.

Does anyone have a part number for the conversion u-joint?

 

[RLDSL]

the yoke is different because the later 10.25s have a longer pinion.

the swap itself is as simple as it sounds. u can take the limited slip from ur old rear, blow off the ring gear bolts, transfer the tone ring and bam.

Err, it's a bit more complicated than that... at least if you do it correctly and want the thing to last and not make terrible noises. There's a reason rear end shops get $1500 or better to set up a rear end.

to do the swap properly requires a dial indicator, inch lb torque wrench and a number of other goodies to setup the gears and crush sleeve properly, and if done incorrectly the gears will eat themselves up
You can get by with just a dial indicator if just swapping out the carrier, but he's wanting to change gears and that requires a complete setup.

 

[MUDKICKR]

if you were near WV id set up the gears for 150 bucks. easy to do but i do it for a living. in your position your better off switching out rear axle assys and leaving the gears themselves alone.

 

[u2slow]

I've never had a truck with a locker before actually...the limited slip seemed pretty stout to me.

Yeah, its just something I think about when I'm diff shopping

 

[gonecrazyi]

I swapped a 96 rear under my truck and it bolted right up without any need for differnt ujoint.

 

[JwS]

I swapped my 4:10 for a '95 3:55, the only real issue was the driveshaft yolk, but the driveline place I got the rear end from just put the correct flange on the end of my driveshaft with a new spider, I got the rear for $700 brand new! sold my old one for $200. Look on Ebay, that is where I found it. It would have taken me a week (or $600)to swap gears probably..
JwS