4.0 4x4 Regear to 4.10

Assembled 3rd member is 665.
Assembled clamshell with new bearings, solid spacer, and cv bushings is 890.
True track is 450

total is 2 005 plus a 400 core charge for each.

 

Thanks for the reply @urban

How much fuel economy can one expect to get back from regearing? I just bought KO2s that measure 33.25" in diameter and I'm seeing 16.3mpg average with exclusively all highway driving around 70mph. To give you a comparison, I was yielding about 17.8mpg prior to this point with my 31.6" Nitto Terra G2s. Is there any way I could once again see close to 19mpg? Is that realistic with 4.10 gears on an auto Taco?

 

4.30 would be the way to go in theory. But I've read nobody makes a 4.30 for the front diff on the Tacoma. ?

I've only seen 4.10, 4.56, and 4.88.

 

Agreed, 4.30 would be nice but I haven't seen that at all.

From what I'm calculating, a 4.10 with my 5th gear in the automatic puts my final drive right at 2.952 final. The 4.56 gears result in a 3.28 final drive. Stock is 2.69 final. With the 4.10 gears and a 33.25" tire the effective gearing would be only just slightly shorter than stock gears and the stock 4x4 Pre-Runner tires. That's right about perfect. I want my fuel economy back!!!

 

"Let's Make Fuel Economy Great Again!"

This is why I need to do 35's.... so my gear ratio will be closer to stock again... so I can save fuel usage... yes. That's why...

 

Haha, yes! But seriously, i went full nerd mode and saw it's a substantial savings.

If I get 16mpg average right now (after the bigger tires) and I could net 19mpg average I could recoup the cost of regearing (including labor) in less than 50,000 miles. The math works out like this...3125 gallons used vs 2632. That's 493 gallons saved. At the current price of gas ($2.19) that's right about $1080. So if you plan to keep the truck 50,000 miles or more it makes sense to regear because it will save you money in the long run and it will yield better performance while driving.

At least that's my current logic thought process.

 

Plus saves wear on your transmission.

 

in my research for gearing i have found taht the 8.0 clamshell has two different carrier sizes. 3.73 and down and 3.91 and up. a company called nitro gear makes a 4.3 for the 8.0 e-locker rear diff. the also make thick cut gears in 4.1 and up that will fit the 3.73 and down carrier. i have found that gears for the front are very pricey.

 

If you have a 2x4. a 4x4 is 2k, plus if you live in som place salty and your trucks seen a few winters count on alot more than that. The bracket on my parking brake cables disintegrated when I took it off the rear axle (this being I dropped the whole axle to paint it and work on the leafs) which is about $300 to replace both sides, my brake line stripped becuase it was in fairly rought shape another $40, plus the big one is I had to use a slide hammer to get the rear wheel bearings off which pretty much will destroy the bearing race. That was an additional $600 plus another $100 in labor if you don't have a press to have the old ones taken off and the new ones pressed on. If you are approaching this from an economic standpoint, don't fucking start modifying your truck and just drive it.