Gear ratio

I recently purchased a 2004 CC. Truck is lifted on 33s and has a 488 rear gear. Plenty of torque on the bottom but on the highway it turning a little high. Right at 3k at 70 mph. Can anyone recommend a good gearing that will keep the rpms around stock form with these wheels?

 

2wd or 4wd? If 4x4 you'll have to do front and rear to keep the drivetrain working.

Also was correction for the speedo done to match the gearing? With 33's and 4.88's 3k is 80mph. 2.6k should be 70mph.


4.56's would be 2.4k @ 70mph and 2.7k @ 80mph.


Acceleration will decrease by going to taller gears in exchange for lower freeway rpms. If you tow it will make an even bigger difference.

 

Factory is 3.91.

You are at 4.88.

Probably 4.10- 4.30 would bring back the factory RPM on 33’s.

 

That’s a really good gear for our trucks already but if you want to gear it to rev a little less on top you will want 4:56 gearing.

 

The diff I got from an 04 DC (she refers to hers as CC, which hopefully means crew cab). Was 4.10s stock, like Sequoia's come with.

4.30's with possibly some loss of acceleration or 4.56 may be a good compromise IMO.

 

Yeah. All I’ve read is the 4.56 is the best compromise for 33ish tires. She was asking about getting back to stock RPM so the answer I gave was based on that. If I ever do gears, I’ll do the 4.56.

 

Oooo I’ve got an idea. Ive been wanting to re-gear to 4:88s because i have 35s, and i have a limited slip Differential with 4:10s i think, and we could trade.

 

Let me ask you this, are you reading your MPH on your speedometer and are you a true 33?

I have 34's and 4.88 and at 70mph on my speedometer and my RPM's are about 2650-2700 BUUUUT my true speed isn't 70, is 77 according to my GPS. On 04-06's, we get our speed from the ABS sensors and re-gearing doesn't close the gap like the old way. The truck thinks its traveling 70 but the RPM's are true, it doesn't make sense but I've done so much research and called Nitro-Gear, Just Differentials and serval local gearing shops to confirm my thinking.

According the Nitro-Gears calculator.

4.88, 33's and 77MPH your RPM's should be around 2678.

https://www.nitro-gear.com/Articles.asp?ID=259

 

I am only reading from the speedometer. They are true 33s. So you’re saying with the speedometer reading 70 it’s an actual of 77?

 

I don't know what YOUR speedometer is reading but it's not accurate. Do you have the WAZE app? If you do, turn on the speedometer setting and compare the GPS speed and your speedometer.

 

Best gearing tool out there....you only need to do Steps 1, 4 and 5 for what you want to figure out....

http://www.grimmjeeper.com/gears.html

 

So @Gdk5514 If your GPS says you're traveling at actual 70MPH, your RPM's should read about 2500RPM. Sounds like your gearing is good. If you're concern, give Nitro Gear a Call, they're very helpful.

 

That sounds about right to me. I'm rolling 33s without a speedohealer and use my phone app (google maps, any speedometer app, etc) to display the actual speed.

 

Michelin LTX 285/75/r16 (32.8’s) require me to add 8% to my speedo reading needle.

Speedo at 60 means I’m doing about 64-65mph. Same with the odometer.

I’m on stock 3.91 gears so my RPM’s are low at highway speed. Good for MPG.

 

How is the towing? I own a boat which weighs approximately 3k with trailer

 

My truck? Tows pretty good. Probably would be better based on everyones feedback with higher gears. It doesn’t suck because our torquey engine likes to pull, but could be better with gears. I tow regular in the 3-4k range. I don’t like going heavier because our brakes suck over 4k. Something about pulling more than the truck weighs is unsettling although I have done it on short trips at low speeds.

 

I just pulled the VIN on my last 04 tundra (stock Toyota alloys). Found it had a 3.58 gear. So which ratio would get me closer to that rpm on the highway? Keeping in mind the last one was a step side access. This one is a crew cab. Which is heavier.

 

Thank you all. Very helpful

 

I'm not familiar with any Tundra having 3.58 gears? 3.91, 4.10 and 4.30 I thought was all that was available?

 

According to this, if I’m looking at it right. It was 3.58

 

Looks like it has 4.08s...

 

Call the dealer and give them your VIN and they should be able to tell you for sure...but I'm confident it's a 4.08...of course you can always be 100% by doing this on the off chance it's been changed since new...

https://shiftsst.com/blog/post/how-to-determine-the-rear-axle-ratio.html

 

Would it be different for an access cab?

 

Plug your VIN into Toyota's website, it may tell you:

https://www.toyota.com/owners/my-vehicle/vehicle-specification

 

yes, but not by much....

 

Only ever seen a 3.58 rear end for a Tacoma.