Looks like I found a swap candidate with an e-locker. Axle code VZNI85L – GPGKA w/265/70’s = 4.10

Any special tools that I will need? Any spring compressors or anything weird like that?

Some of you may already know that I have decent mechanical ability. Headers, shocks, etc are no problem. But, this could be a whole different ball game. I have never done anything like this.

Please let me know what I am in for. Thank you.

 

Congratulations Christian! Just from contemplating what is back there and since you are swapping them out, it should certainly be a good DIY project. I would recommend an extra set of hands cause I do imagine that axle would be a bit heavy to lift and install by yourself. Keep us posted and good luck!

 

I am tempted to buy the rig and keep it...but its an auto.

It is so sweet. All records, recalls, etc. are documented. The only thing I can find wrong with it is a small dent in the drivers side rear bumper cap.

After I perform the surgery, it will be up for sale here on Yotatech. It better have ABS or I am out of luck. Forgot to check that!

 

If Albuquerque Jim doesn't see this, drop him a line. He did a similar swap recently.

 

Yeah, I am hoping he chimes in...

special tools are my main concern.

 

No special tools required. The swap is pretty straight forward. Have a few sets of jack stands and nice floor jack. An extra couple of hands is nice too.

Make sure you bleed the brakes when you are done (it's a good opportunity to extend your rear brake line too, I just added another stock hose to the existing one). The hardest part for me was connecting the Panhard rod after the swap, because I don't have a drop yet. We just put 500lbs in the back and things lined up again.

Get the wiring, ECU and Switch that will make wiring it easier. Have you read Phong's write up?

I would go though the hassle of checking the diff ratio. Because that axle code shows up for 2 ratios:
Especially if it's an auto, I would tend to think it had 4.30's. If it does have 4.30's then just swap both front and rear. The front can be done without pulling the CV's out of the spindles. It's just a little tricky. If you go this route I'll give you a few tips.

But all in all the rear axle is pretty easy.

 

Thanks Jim. How can I confirm the gear ratio - for sure (besides tearing into the 3rd member)?

 

It's not 100% accurate, but it should work. If you have access to both trucks, there is the "spin and count" method:

Block the tires at one end of the vehicle to keep it from rolling, and then jack up a tire on the other end.
Place the transmission in neutral and release the parking brake.
Spin the tire exactly TWO full revolutions while at the same time counting exactly how many revolutions the driveshaft spins (marking the driveshaft and tires beforehand will make it easier to count revolutions).

The number of revolutions the driveshaft spins is your gear ratio.
If it spins just over 4 times, then the ratio is probably 4.10;
If it spins 4-1/3 = 4.30;
If it spins 4-1/2 = 4.56;
If it spins just under 5 = 4.88;
If it spins 5-1/3 = 5.29, etc.

If you have both trucks there you should easily be able to tell if they are both the same ratio or not.

 

If you tape a string to the drive shaft you can just count the wraps then add the partial revolution. You can also do this without jacking the truck, just roll the whole truck one tire revolution.

 

I have read Phong's write-up in the past, but his site appears to be currently down. So, I have to ask about the ECU. The donor rig is an auto, am I stealing the auto ECU? What exactly am I taking?

Maybe I should just go with the inchworm kit?

Keep in mind that the donor rig must be put back to stock, minus the locker of course. What is the best way to accomplish this?

Thanks again everyone!

 

I don't think that the swap will be too hard. I thought that the Locker ECU was its own unit, not part of the engine ecu..


Another option is to give me the rear-locker, i have an auto

 

The ECU is just for the locker, it's behind the driver's kick panel and it is held in with one bolt. It looks like this: Locker ECU

I don't know how integrated the ECU is with the other 4x4 components and ABS. So going back to stock is a question for me. It might be better for you to leave the ECU in there and use another one for your truck. (I have an extra if you are interested) You can always unplug it and see how everything still works.

This was the easiest option for me because I was prewired, I had the ECU plug and the switch plugs already. I basically plugged them in and ran 6 wires to the back and my wiring was done (exactly like Phong's). Have you checked to see if your truck is pre-wired?

If you look around on the net you'll find a few other wiring diagrams from people who have just created their own. I think it's about $10 worth of relays and switches, that's all.

 

Thanks again Jim. The only thing I have left to check is the gear ratio. Then its a done deal. If anything I will at least get the axles swapped over and go from there.

I appreciate everyone's insight thus far.

 

I would pull the ECU, switch, and most of the wiring from the donor. The e-locker ECU is a totally isolated unit. Just pull the ecu and snag the plug with pigtails and wrap the loose wires in the donor truck with tape and nobody will ever know. Same thing with the switch - just snip off the two wires (leaving as much wire attached to the plug as possible) and pull the switch.

The wiring from below the rear seat to the locker may be a bit of a trick because the ABS wiring is integrated. Very doable if you swap your harness into the donor rig but it would take some rewiring. You might be better off just using the e-locker harness and custom-wire the rest of the way to the ECU.

If you want the dash light to engage, then pull the dash, snag the bulb, and steal the appropriate wire with metal tip.

One of may write-ups:http://www.geocities.com/transalper/lockers.htm

 

Hey thanks Jay, that helped a lot. I just printed one of those write-ups out.

I just thought of another question: So when I go to "drop" the axle after everything is unbolted, what separates the springs from their perches? Does the axle just pull away from the springs, or am I going to have to unbolt/unclip something?

 

Nice Write up.

I guess I was very lucky to be pre-wired. I plugged in the ECU (existing harness) and the switch (existing harness) and the light on the dash came on.

The springs will just fall out.

 

Nothing to unclip with the springs. Just taking off the shocks and disconnecting the sway bar can give you enough room to take out the rear springs.

If the axle ratio doesn't work out, let me know, I may be interested in doing the swap!

 

Are you 4.30 Travis?

 

Hey Christian-

I agree with what Jim said earlier, if it is 4.30 and not 4.10, just swap the front, too. Something to think about...

 

Jayson -

I know...but 106 degree temps tend to put a damper on things

Well, I will most likely do that, if 4.30 is the case. My co-worker and I went out in the parking lot and did the test this morning to the rig, only problem is we only did one rotation of the tire instead of two like I was instructed to do But, it looks like the shaft went around just over 2 times.

We are doing the test again later.

I don't even want to think about swapping the front diffs out right now.