The 4.88 mega thread!!

Good ole central Ohio, not the most ideal place for Tacoma-lovers.. but my question isnt so much if it's better but more what my MPGs will look like and added stress on the drive components. Anyone on this thread will say to do it but if it won't help anything except for "feel" then I dont need to spend $4000 on feel

 

I have a lot of respect for the folks who understand how rpms:gear, fuel mixture, and engine:tranny combos affect the bottom line on gas mileage.

I'm a novice in those areas and would never discount what you know about the mechanics of gearing, but what I can tell you for sure is that how hard you press down on that gas pedal has more of an affect on gas mileage than anything. The reason gas mileage gets so much better with Tacos when you add gears and OVT is that you can feather the gas pedal and still keep up to speed. The stock configuration has you constantly pressing and releasing the gas pedal to control the erratic shifting and lack of low end torque. Gears and tune fixes all that.

 

Scs f5 16x8 3.5bs, 285/75/16 cooper st Maxx.

 

Jumping in here... Just re-geared to 4.88s and got 2" suspension lift and 33" MT tires. Used to get around 18 - 20 mpgs, now getting 11 - 12 mpgs first couple hundred miles. I knew I was going to take a hit, but this seems excessive. Anyone else have it this bad ?

 

Were you stock before?

 

Seems the gear ppl are saying that 5th and 6th gear are rarely utilized on the 3rd gen with auto trans and regearing will help you use those gears. Lol. I also have a jeep and gears are usually one of the first set of mods u do. My mpg went down too. I've only had my taco for a year and a half and havent tested the theory. At sea level I'm not getting too great of gas mileage and only have 32s but the truck could use a regear! It prob should've been made with 4.30s or 4.56s factory. The difference in gearing from stock to 4.88 is roughly 25% so ur loss of mpg are about right all things remaining equal. Just dont forget about added weight like wheels, tires, skids, and sliders. Even the rubber bed mat, lol. Check if ur using 5th and 6th gears... There's no doubt the truck is running easier with the gearing, less stress on the drivetrain. Let tw/us know!

 

Must be a LOT of short trips enjoying the gas pedal. Not directly related but did you do a break-in period?

 

11-12 seems a hair low. In January 2020 I put in 4.88s but was only running 31.6s. My mpg was usually 17-18. Ovt will help with shifting, which may help a little. The tune will make sure you're staying in a gear that actually keeps pushing the truck rather than mashing down the pedal and getting it to downshift. When I did the tune last August my mpg went up to 18-20 mpg.

That said, what width are your 33s? M/Ts are usually pretty heavy. If you got a 285 with C or E load I wouldn't doubt the mpg took a big hit. Weight an aerodynamics make a big difference with these trucks. I was getting 18-20 a month ago, but just had a GFC installed. Now I'm at 13-15.

 

@Stocklocker Yes, it was full stock before.
@GOLIVER0131 Yea, I hit 6th gear for the 1st time I can remember. I have an AM steel bumper as well which doesn't help.
@Pablo8 Nah, no explicit break in period. Was planning to take it back in the shop around 1k to re-torque and have em check it out.
@Kerbouchard! A tune sounds like a good idea, this the recommended one ? https://vftuner.com/collections/tune-packs/products/tacoma-3-5l-vf-tune-pack

Im running 33x12.5s with C load so they're mini tanks.

 

Short story, yes, VF Tuner is what you want.

Longer story--there are tons of nuances involved. It's not a super straightforward process because the software, tuning, and pricing options have been changing a lot over the past year. I don't want to bog down this thread with the details. Poke around on these threads...there are a few guys involved in each that can get you direct answers on how it all works now:

https://www.tacomaworld.com/threads/vf-tuner-for-the-3-5l-tacoma.662948/
https://www.tacomaworld.com/threads/new-vftune-install.671072/
https://www.tacomaworld.com/threads/best-gen-tuning-and-bs-more-bs-than-tuning.693221/

Edit: You may not need to buy the tune pack if you just want to flash one of the new tunes that TW members have created. You can also pay someone in your area to flash your truck.

 

Like many others, I’m torn between 4.88 ad 5.29. I’m planning on running 34s (275-85–17 33.86). NITRO recommends 4.88 on 33s and 5.29 for 34 and above. Yet duvinclunk (post #1445 this thread) watched TAV videos and called them. TAV Uses 5.29s on 37, 4.88s are a perfect gear on 35s and had a customer with 33s and a 4.56. I made a 600 mile run 3 weekends ago and ran at 75 80 MPH a lot, all stock, not loaded. I ran 2000 RPM at 80 and the was at 19.2 MPG on the last tank and above 19 overall. So the question is to balance the power you need with larger tires and not kill MPG. Is 4.88 overkill on 33s expect in only the most extreme conditions or you have build a serious crawler? Is 4.88 enough on 34s or 35s like TAV stated?

 

4.88’s and OVTune towing 500lbs today.
love the gears. Tuned is another world.
Hit up @PapaRee or @Mooseditty17 for tune info if interested in upgrading.

32’s (255’s). With the right combo it’s crazy what this setup can do.

 

RPM is simple enough to calculate, see the tables below. I’m still trying to figure out the balance of power you need for a larger tire vs maintaining some semblance of fuel economy.

 

Trans temp is looking good, what app is that? I have used OBD fusion and Torque and I'm not thrilled with either.

 

OBD Fusion
(customized gauges on my end)

 

Are you going to VFTuner to fix the speed limiter (edit: for possibly 5:29's)? Also, what is the long term weigh expectancy? Sorry if I missed it...

 

Good job, it looks very slick

 

I’m stock 2021 double cab off road at this point. I have VF Tuner on truck now mainly to correct the throttle lag. My expected build is 2.5 inch lift, front and rear bumpers, winch, ARB twin under the hood, sliders, with 275-75-17 Toyo AT3 with either Black Rhino rumble or Method 316 wheels. I don’t know yet what else I may add. Wheels and tires selected for weight savings.

My son has a similar truck already converted to a 5.29 with Nitto Ridge Grappler 34s and KMC KM101 wheels. I’ll have 12 to 15 lbs weight savings on the wheel tire combo I’m going to get. I plan on running a while without the gear change and then deciding on 4.88 vs 5.29 after wheel and tire change.

See post #1496 for RPM tables. Nitro has a video that says 4.88s are perfect for a stock truck. That would make a 5.29 a no brained for 34s when you look at the RPM. Row 89 vs 94. Nitro also says 4.88 for 33s, row 91. TAV said 4.56 for 33s row 90, 4.88 for 35s, 5.29 for 37s. That would make a 4.88 for a 34 analogous to the TAV builds if you look at the calculations.

 

If you have an AT - pretty much always get the 5.29. The only exception MIGHT be if no loads and never off road.

 

Even with 32's?