So recently I found a deal on a lightly used set of ARB front and rear lockers with 4.71 gears setup in 3rd members, and they're a damn good price. Being that I currently have roughly 32" tires (265/75/16), what do you think of this setup? I was going to do 4.12s but maybe more is better

I've got a 95 disco V8(auto), and I already have HD axles, A Tom Woods double cardan front driveshaft and will be getting a double cardan rear of the same make with the U-joint conversion...

I know this setup is pretty overgeared, but being that these motors have such very little ***** and being that this not usually highway driven, I'd love to feel some torque... You think this is livable, or are gear changes going to feel like a mule kick?

Ashcroft's gearing calculator is telling me ill be jumping from a stock 2500 rpm at 70mph to nearly 3100rpm...


Thanks,
Chris

 

Yea, it would be singing at 70, but I can imagine it would darn near climb a wall. Gas mileage would suffer, but the fun level would increase. If mine was a toy, and I had the upgrades you have, they would be in my garage itching to be installed.
Let us know what you decide and if so, your experience.
Thanks

 

You should use this.
Ashcroft Transmissions - Ratio Calculator
Basically with 4.71 gears and 32" tires at 60mph you be pushing an extra 500RPM over stock gears(3.54) and stock(29") tires.
Even if you ran a true 35" tire on those gears you'd be 200RPM over stock.
If you have a trailer queen, go for it. Otherwise, 4.12 on 33's or 34's, even 35's is pretty good.

 

Thanks for the boot of confidence Joemamma1954, I'm eager to try these wall climbing abilities

And FishEH I used that calculator its great stuff. By no means is my truck a trailer queen haha, but I think for the price I'm getting and with the benefits of low range crawling and torque I'd be getting from it (not to mention having front and rear air lockers) it would be worth it.

I just wonder if there are any other strains I'd be putting on the system by having such short gears... you'd figure not since most of the new found torque is after the diff.. but it's never that simple.

 

axles shafts & cv joint

 

How much lift are you running? Typically you won't need a DC rear shaft till you hit 3+" of lift.


3100RPM's cruising on the highway would get pretty annoying I think.
But seeing as how the thirds are already set up, might as well drop them in I guess.

 

Already got em, Tibus front and rear.

 

Thats the spirit!
And I'm only at 2" of lift right now but I know I'll be looking to 3-4" in the future and I'd rather have it all setup ready for that.

 

I was cruising to a Rover meeting yesterday and was pulling 2270RPM @ 65mph on stock gearing and 235/85/16's. I can't imagine 3000RPM would be fun.

 

If you're planning to stick with the 32" tires I would recommend against the 4.71's. I'm running 4.75's on true 35.5" tires and the RPM's are noticeably higher at highway speed. Still manageable but still high. Fortunately, this is a trailer queen and does not typically see the highway so it works well for me.

I had a friend that ran 4.75's with 33x12.50's and he was running 3,000 rpms at 65ish.

At 32" tire you really want to be looking in the 4.1x range. If the lockers are really that good of a deal you can always buy them and switch to some 4.11's and sell the 4.71's. Or just upgrade to a 35" tire.