Lockers & Regearing

[OverlandExpy]

Its been a little while since I've been able to work on my rig, so I've just been doing research on what parts to buy next. Unfortunately we've been having record setting rains in NorCal lately and my shop/hangar is leaking like a sieve, so I've been dealing with that (and spending plenty of money).

The plan is to regear with 4.56, then put eaton detroit locking diffs in the front and rear. For the gears, I was planning on going with a full rebuild kit from Nitro, specifically the part # GPF150-4.56-FSJK.

For the lockers, the plan is to get the eaton detroits, 9.75 34 spline in the rear, 8.8 28 spline in the front. Part #'s: 187C147A & 225C194A.

I've searched the forums a bit but haven't really seen any write ups of anyone who has installed them. Was hoping that someone has put at least one of these things into their expy's. I'm 95% sure everything listed is the right parts, but just wanted to do my due diligence before I pulled the trigger on everything since it'll cost $2500 + just for the parts.

In the meantime, rock sliders still havent even gone on yet lol. They've been sitting in my shop collecting dust after I made em. The other shop I do some metal fabrication in a few days a week just bought a cnc plasma cutter, so I am planning on designing and building some skid plates, first and foremost for the gas tank which practically sits below the cross member. If anyone would be interested in some skids, let me know. I'll make sure to update my "Balls to the wall" thread that I've been posting all my build updates to.

 

[Vincent Vega]

@OverlandExpy, Sometimes it is frustrating because of the lack of good aftermarket products and info for our rigs. It's all about the Jeeps and Toyotas (junk). However, @Starkman has installed Eaton Trutracs on his Gen 1. He also has a Youtube channel called Stark's Expeditions, including a video on his experience with the Trutracs. Not sure if this helps, but hope it does. You have a good project, thanks for posting the updates.

 

[OverlandExpy]

I saw that, thank you! His videos were super helpful for sure, but I'm looking at the detroit lockers. The lack of good aftermarket stuff definitely is frustrating, at this point I'm just working on my fabrication skills because it looks like if I ever want beefier upper control arms, or anything else really, I'll need to make them myself lol.

 

[Vincent Vega]

I saw that, thank you! His videos were super helpful for sure, but I'm looking at the detroit lockers. The lack of good aftermarket stuff definitely is frustrating, at this point I'm just working on my fabrication skills because it looks like if I ever want beefier upper control arms, or anything else really, I'll need to make them myself lol.

@OverlandExpy I may have mentioned this before, but I wonder if F150 UCAs might work. There are aftermarket UCAs available for 04-08 F150s. Factory UCAs for Exps and F150s are different (or at least have different part numbers) but I don't know by how much. Seems like they would be similar enough that you could make it work, especially with your fabrication skills.

 

[OverlandExpy]

Unfortunately they don't fit, the frame mounts are in slightly different locations. I guess I could cut and move the mounts, but the less messing about I have to do with the frame, the better. The guys I work with when I'm doing metal fabrication know how to make some custom ones though! Granted they usually are rebuilding classic cars and hot rods, but the principle is the same. Apparently it's pretty straight forward. But I still need to put on those damn rock sliders I made months ago, and I'm waiting for our cnc plasma cutter to be operational so I can make a skid plate for the gas tank.

 

[Vincent Vega]

@OverlandExpy regarding the lockers, are you worried at all about snapping CV joints in the front after lockers are installed? It would put more stress on the CV on the side with more traction. On the other hand, an open diff will spin the hell out of the wheel that is off the ground (this happens alot with our IFS), then put alot of sudden stress on the CV when that spinning wheel hits the ground. Any thoughts?

 

[OverlandExpy]

@Vincent Vega for sure, that is an easy way to snap the cv. Just gotta be careful when one wheel gets off the ground, and you do NOT want to come back down when the wheel is spinning. When I'm offroading and in that situation, I put one foot on the gas, and one on the brake. I keep the gas pedal depressed slightly, not much more than 2k RPM, and keep it fixed in place. Then I use the brake pedal as the "move forward" pedal by slowly releasing pressure from it. Keeps the truck controlled when dropping off an obstacle so it's not jerky and no sudden movements. But I also plan to go to the local pick n pull and pick up a few spare CVs to take with me on the trail just in case lmao.

 

[OverlandExpy]

@Vincent Vega But to answer your actual question lol the expy was designed to tow a shit load, so the CVs can handle really high static loads, it's much more likely to snap under a sudden dynamic load. The lockers would keep a more constant force, and you'd really need to gun it when youre pinned or be at full lock and full deflection at speed or something like that to break it IMO. And you don't run the risk you do with the open diffs of spinning a wheel that's off the ground and coming down on it and snapping the cv.