4.56 or 4.88 for 34s with Armor

Hey all,

I've searched through a ton of regearing threads and asked a ton of people who have regeared, but found no definitive answer on this. I plan on regearing my truck here in the next two weeks and put in lockers, however, I still haven't decided on which gear ratio to use. I have a 4.0 DCSB automatic tacoma at the moment running 34 in tires (E Load too so they're heavy... 95 pounds per corner of the truck)... With all my armor, rear bumper, equipment, roof rack, camper shell, and decked system, I'm looking at an additional 1000-1200 pounds extra that I carry every day. I am currently stationed in Colorado, however, if everything goes to plan, I will unfortunately have to move down to Texas in a year and a half/ 2 years.

Now as for the truck usage, I love to go offroading, however, the truck's number one priority is highway driving as it is my daily driver. I am consistently making 300-500 mile round trip going 75-80mph every week or so. My priority is trying to decrease the RPMs at those speeds and try to get a little better mpg. Currently, the truck likes to either, stay in 4th gear and cruise at 75-80 mph at 3200-3400rpms or will go into 5th gear at cruise at 2500 rpm, but won't be able to keep the constant speed. As for any sort of hills, the truck will go into 4th gear and have to maintain speed (or most times decrease speeds) at 4000-5000+ rpms. I average anywhere from 200-250 miles a tank, so roughly 13-15.5 mpg at the moment. Any sort of headwind or hills absolutely kills the fuel economy.

What do ya'll recommend? I've heard that 4.56 will bring the truck back to stock ratio, but at the same time, I heard it's too low and still won't compensate for the bigger tires, extra weight. On the other hand, I've heard that 4.88 is just right, however, the truck will be screaming (high tachometer) at highway speeds. What do ya'll think for my situation? I'd be happy to hear any personal stories/ suggestions. Thanks!

 

I have full armor and 34s as well and went with 4.56 and I’m really happy with it. I know your frustration with the stock gearing now I can cruise at 75 @24-2500 in OD. Went from 13 to 15ish mpg the drivability is way better and maintaining speed on hills and passing other cars on the hwy is almost better than when truck was stock.
If you dream of 35s I’d probably go 4.88s.

 

I may potentially get 35s, but that won’t be for another couple years as my 34s only have 9k miles on them currently and still look brand new

 

5.29's for Colorado for sure!

 

My vote for your needs is 4.56

4.88 and 37s and I drive slower on the highway due to the rpms

 

I think it would be more useful to submerge the air intake in water at that point

 

Awesome thanks! I’m learning towards 4.56 at this point to keep highway speed rpms down

 

Gonna Piggy back on your thread. Almost same set up. But want 35s

I’m currently stock looking to re-gear and I’ve got a lot back and forth about 4.56 and 4.88..

i like to hear from someone who has run both and get their input.

 

Think about what you just wrote. In order to make the power required to keep the truck moving at highway speed, the engine has to to turn over 3,000, and any hill requires the maximum output potential of the engine. If your truck is barely maintaining speed in 4th gear, how is regearing going to help? You are either going to have to slow down or lighten your load and tire weight/size. New gears do not create horsepower. Gearing can help marginal situations by moving the engine speed higher in the power curve, so the engine is not struggling. You are way past marginal. Honestly, I would quit pushing the truck that hard and get a little car for those 80mph runs. Things will improve a bit in Texas because of the elevation, but it's still asking a lot of that truck.

 

Right, I completely understand and agree with that analysis. My assumption is that gearing will help a little bit with those high rpm settings. I realize that with the altitude, weight, wind resistance, and all the over mountain passes that I am pushing the truck hard. Just trying to get it a little bit of a push/help in doing so by regearing... Regardless, I want to put in lockers so I've decided that I should regear at the same time

 

It makes sense to do gears with the lockers, just be careful. You might end up with a 5th that is still too high, and now a 4th that is even lower! You could end up worse off!

 

Any other input to this? Personal experience?

 

I’ve got tall 33’s and I barely use 5th gear. If you gain 500 rpm back you’ll be able to cruise in 5th at a more comfortable rpm vs 4th at high rpm. It seems counter intuitive.

 

What gears do yall suggest if going to 35-37s, from stock 32s?

 

I have a 2007 Tacoma 4.0 with 4.56 gears, 305/70-17 (34”) tires.2500 rpm going 80. I also tow a 5000lb boat with it no problem at all. I think it’s the perfect gear ratio, slightly overgeared but if you tow or Cary a lot of weight its a game changer. I also get about 16mpg

 

i have a 2015 v6 DCSB with 35" super swampers. i ran the 35's with the stock gears for 2 years. In 2017 i finally re-geared to 4.56's and i could not be more happier. I would steer clear of 4.88's no matter how much armor you want to put on there. The only reason i say that is because even with 4.56's, you will notice a substantial increase in RPMs on the interstate.

 

No shit even like the op mentioned with 1000-1500 lbs of weight?

 

Really? I thought regearing would help with interstate rpms

 

Keep in mind there are different variables to consider between AT, MT, and also second and third gens.
Manual trans and or third gen experience is not the same as a second gen with auto.
Also, there are 4.30 and 4.10 options that were not available a few years ago.