2.7 Re-Gear

2011 2.7 Access cab 4x4 auto with LCE header, Pro dry filter.
Live in hilly area and tranny constantly drops gears on slightest hills. Would like feedback on re-gearing from 4.1 to 4.56 ?
Any feedback from people who done this? will it hold gears much better? how much will it hurt mileage? I do 50 - 50 city / highway and get 19 -20 mpg currently.
what is the cost parts & labor and who sells this kit?
thanks

 

You are a 4 cyl 4x4 so you already have 4.10's.

I have the V6 so I started with 3.73's. I went to 4.88's and my tranny rarely wants to down shift on the freeway now (I have oversized tires) where before it rarely wanted to up shift at 75mph. I lost 1 mpg at the most, 4 cyl may be affected differently though so not sure.

I got mine from East Coast Gear Supply. If you think you can set up a ring and pinion yourself, then you can just by the gears sets and install kits and go at it. I didn't trust myself to set them up though, so I ordered the pre-assembled diffs and then swapped the diffs out myself. Cost me about $2250 counting shipping there and back but I also bought an ARB air locker for the front diff for $900 of that $2250.

 

do you mean it downshifts from OD to a lower gear, or does it downshift no matter what gear your in besides OD?

My 2.7 5spd would climb hills fairly well in 5th while going 65+ but any slower and I would have to drop to 4th. Now that I did the lift & 33's I need 4.56/4.88's in the worst way!

 

Yes, when in overdrive (4th) it constantly downshifts on the slightest hills at 70 mph. I am beginning to just drive it in 3rd more and more where it's hilly in my area. It seems fine from 0 to about 45-50 mph, it's mostly freeway driving that has me vexed 50% of the time. Guess I could sell it and buy a 4.0 but I get attached to my stuff.

 

What size tires are you running? factory?

Oversized tires on the 4.0 will result in the same problem...

 

Stock OEM tires

 

I have 4dr 2012 pre runner,2.7 auto Just keep it in 3rd,OD when you need it .Or I drive mine at 80 most of the time in OD .when it slows on a hill.Just pull it back to 3rd (keeps top speed) Even that it has a 4.10 gear,i have had it over 90 in 3rd gear,yes it could use 4.56 even with stock tires.

 

this is what I was going to suggest. Most vehicles will downshift from OD on hills while trying to maintain a constant speed.

 

basic install kits, that shit's brandy new!