F+R 4.88's with ARB RD-90 front locker
I never really posted much on my re-gear and front locker install, and I don't have the time to do a full write-up on everything, but I figured I'd post some of the few pictures that I took during the process.
I started with this pile of parts... An ECGS built front 3rd with Nitro 4.88 R&P and an ARB RD-90, ARB CKSA-12 air compressor, rear e-locker with Yukon 4.88 R&P, and a spare 4.10 geared stock front 3rd.
The spare 4.10 front 3rd went back to ECGS, and I have kept my stock diffs as spares.
Pulling the front diff was another one of those jobs where I thought to myself, "What are all those people whining about? This isn't too bad." Going from tires on the pavement to diff on the floor took me an hour and a half.
It took me another 1.5 hours to strip down the old diff and swap all the components over to the new one.
The hardest part was stuffing the new diff back into it's home. The process would be a piece of cake with two people (and/or a 4-post lift), but doing it by myself, on the ground, left me with several large bruises on my legs and a sore back. Nonetheless, I got it mounted up in about 2 hours.
After that I moved to the rear diff, and had the 3rd pulled in short order. I was making fast progress until I checked the rear wheel bearings and found that my passenger side rear wheel bearing was on it's way out. An order was placed with Toyota of Dallas, and the parts were on their way. I had my mechanic do the press work on the axle shaft and 2 weeks later I was back on track.
Both diffs got filled with this for the break in period:
Both diffs were broken in according to the instructions from ECGS. I started with a series of many short, easy drives followed by cool down periods. Then I started taking the rig on longer trips and putting some miles on the gears. During the Ouray trip I put a healthy amount of 4WD miles on the new gears, toward the tail end of the 1500 mile break in period. The rear diff already had 2500 miles on it, and had been through a full break in process when I purchased it, but I decided to treat it as a new diff since I was breaking in the front anyway. Everything ran smooth and quiet, and the difference in the driving experience was immediately noticeable.
This is how my rig runs with the 4.88's and half worn 285/75r16 Duratracs... The torque converter was locked when this picture was taken, and my ScanGuage is programmed with a 7% speedometer adjustment to account for the change in tire size. The ScanGuage speed readout has been checked with GPS and confirmed accurate.
I didn't bother wiring & plumbing the compressor and front locker until after I'd completed the break in process on the gears. The compressor and wiring were easy to install, and I have to say that ARB has come up with a smooth little system. The hardest part of the compressor install was eliminating all the leaks at the air fittings. The ARB instructions call for the use of Teflon paste, but I had much better luck with yellow gas line Teflon tape. Here's how all that turned out...
I got rid of my "VSC/TRAC Off" switch, being that I have never ONCE turned those systems back on since the day I disabled them. I removed the old switch, shorted the leads, and replaced it with a very small rocker switch which now resides under the dash near the ABS computer. If I ever want to turn the systems on I can reach up under there and flip the switch, reconnecting the circuit. There is no reason to have the switch on the dash taking up valuable real estate.
The "Toyota Security" insert that I was using for my alarm system LED has also been removed, and I'll find a place to drill a hole and place a red LED somewhere else in the near future...
Prior to the Jamboree, I changed the fluids in the diffs and checked the front for proper break in. Everything looked copacetic with regard to the front diff, and I found the typical small metal shavings on the drain plug, but nothing that gave me any concern.
Gear oil showing a nice metallic sheen, thanks to the suspended metal particles resulting from the R&P break in...
The rear diff oil was in great shape, with only a thin layer of gray paste on the magnetic drain plug. It turned out just the way I hoped/expected considering that the rear diff had already been through the break in process.
I refilled the diffs with the same 85W140 Lucas Non Synthetic Gear Oil that I used for the break in process. This is the oil that ECGS recommends running, and I'm going to give it a try through the summer. For the cold months, I may switch back to Redline 75w90, as I've had good results with it in the past. The 140wt is so thick and sticky that I'm concerned it's going to hurt my mileage when winter rolls around.
Speaking of mileage, I was seeing 17 mpg on the highway and about 14 mpg around town prior to re-gearing. After running through nine tanks on the new gears, I've been seeing 15.5-17 mpg on the highway, and 13-14 mpg around town. I estimate that overall I've seen a 5-7% drop in fuel mileage with the new gears.
The difference in power and acceleration is striking. The rig zips around effortlessly now at all speeds, and is much more fun to drive. If I had a stock rig and had to choose between a supercharger and gears, I think I'd probably take the gears. I should have re-geared this thing years ago.
If you have any questions, feel free to ask.
