4.30 rear end gear?

Is there a reason that toyota only offers a 4.30 for the rear end? I'm guessing that's why their city/highway mpg's are 13/17. Don't get me wrong, I don't expect a truck to get amazing gas mileage, but that seems kind of low. Im sure it attributes to the towing capacity of these tucks as well as acceleration. Has anyone installed a higher gear ratio and/or are they available? I've seen a few threads of guys putting in lower gears to compensate for taller tires, but couldn't find anything about higher gears.
I'm currently looking at trading in my 2010 F-150 on a new 2019 SR5 and the only thing I'm not excited about is such a low geared rear end.

 

I don’t think it’s the gearing giving us bad gas mileage, it’s more that it’s shaped like a brick and the engine likes to drink dinosaurs. You might get a little better with some tall gears. What was your actual mileage on your 2010 F150? I’m talking hand calculated.

It seems that the big 3 tend to fudge their numbers a bit. While Toyota is pretty spot on. in their claims.

 

The 4.30 rear gear is only with the Mama Toyota factory tow package.

 

Hand calculated for city was usually around 15mpg, depending in how I drove on that tank of gas and highway calculated usually sat around 18 mpg. My truck had the 4.6 engine with a 3.73 rear end

 

The mama toyota factory tow package?

 

Yes. The gears. The trailer hitch. The trailer hitch electrical ports. The trailer brakes controller. The BEAST MODE tow button.

 

Gotcha, I wasn't sure what he meant by that, but now it makes sense.

 

Why not want a 4.30? That's the main reason that got me into a Tundra...Gm and there 3.08's lousy gearing. I think the Titan is something like 2.91 if you want something along those lines. The bad fuel mileage is the fact its a straight up big v8, and a heavy truck, MPG and this truck don't go in the same sentence.

 

The alternative....GM 3.7s or Tundra with 4.3 and beast mode... and who gives a rat's ass about Tundra mpg's??? That's why there is the Prius option. .

 

I’ve gotten 18.4 mpg (US) highway on a return trip from the BC interior to Oregon and average for the last 10 months is about 15 mpg. 10pr tires over the winter and warm-ups included. Don’t be afraid of the 4.30’s, they go well with the double overdrive transmission.

That’s a stock tundra with tow package, no lift and big boots.

 

This week we have TWO winners of a chicken dinner. Thanks guys.

 

I personally would rather have the 4.30 gear than 1-2 mpgs to be completely honest. I also hope the 4.30s stay around in the next gen Tundra.

 

Thanks for all of the info guys. The reason this was a a question was because I figured there would be multiple rear end options for each engine choice. I guess I have to stop assuming that Toyota's and Ford's are similar!

Hopefully by next weekend I can post a picture of a new SR5 in my driveway.

 

Ford uses their 8 and 10 speed transmissions to regulate gear ratios Toyota has chosen to use a lower axle gears and a super reliable 6 speed transmission. Same dinner different recipe, if you check out F-150 forums you will find a lot of trucks go in the shop for transmission issues. I know my ex-father in laws Raptor has been in the shop 3 times for transmission problems in his first year of ownership. At the end of the day they accomplish the same thing.

 

For what its worth I was in a friends 2018 ford 150 with the nano 2.7 engine. We were cruising on the highway i glased over a seen 16.6 tank average on his display. Give me our big V8 ! For the life of me I couldn't own a nice big truck knowing under the hood is a nono engine.

 

The non-tow package Tundras have a 3.90 ratio.

 

I thought they were 4.10s?

 

My 09 Taco had 4.10. I think.

 

HUH! The saved bookmark where I thought I read this is now gone. This is what I've found, and I guess that you are correct!
http://www.toyodiy.com/parts/p_U_201104_TOYOTA_TUNDRA_USK55L-TRTDKA_4101.html

 

Maybe the 3.90 is offered in the first gen?

 

Could have been. I don't recall any more these days....

 

I’m right there with you man. I wish could’ve retained 30% of the information I’ve read over the years. What I knew as fact at one point in my life has has now become ... I think

 

The only gears currently available are 3.91 and 4.30. All 5.7 get the tow package so 4.30 gears, 4.6 with the smaller axle has 3.91 gears. If I remember correctly the first few 07+ production years had 5.7 without tow package, and that used 4.10 gears.

 

This sounds consistent with what I remember reading... I think.

 

The 4.30s are one of the main reasons to accept the mpg hit... I dont think you can get anything more than a 3.42 in a 1/2 ton GM.
All the other manufactures are putting 2.9-3.40s behind 8 and 10 speed autos that make up for it by CONSTANTLY shifting and gear hunting. My 2016 GMC 8 speed with 3.42s was actually pretty quick off the line with the short gearing of the tranny, got MPGs that everyone says I am making up, @ 24mpg+hwy, even if I was off 10% it would get better gas mileage than a Tundra on its best day.
And I still traded it for a 2 year older Tundra. GMs are the mileage kings, Followed by Ford, Followed by Ram, .....last place Tundra.
GM is also garbage, Ford is $$$$, Ram is Fiat .... and the Tundra is a Toyota! I will say the Tundra and Ram still drive like TRUCKS!
I hope they dont wussi-fy it on the next gen with a bunch of expensive to insure aluminium, Bearing killing cylinder deactivation, mushy highway gears, and slush box confused 10 speed automatics that spend more time in the shop than pulling trailers.

 

Low gearing, big engine and cab room sold me on the tundra. I dont mind the mpg hit since I only drive about 8k/year. I have a company provided vehicle to commute in.

I came from a gm 5.3 and 3.42 gears, it was a pig....

 

Just checked my vin
3.91 Rear Differential w/9.5" Ring Gear Automatic Limited-Slip Differential

 

I wondered the same thing about 4.3 being tall and affecting gas mileage. The final overdrive is approximately 0.5 ratio so the equivalent of 2.15 ratio. A lower ratio probably won't help because the truck shifts out of the overdrive gears 6&7 rather readily going up even small hills with cruise control on.

 

Well after 5 months of owning my 2019 SR5 Sport I couldnt be happier. The power and acceleration is amazing, which has let me look past the mpg's. It tows like a champ and looks down right sexy doing it!

 

You can't compare rear gearing in different truck without comparing the gear ratios of the transmissions as well. The Tundra isn't running at any higher RPM than the V8 Ford or Chevy at highway speeds if they all are getting the same MPG, or very close.

Toyota just chose to make the leverage point in the rear axle more reliable and a larger ring gear means more teeth which over 200,000 miles means more durability.

Transmission is a very reliable finely tuned over the years design, but fewer gears with higher ratios than other manufactures which is why you get the slight hunt for gearing sometimes but trade off is less shifting on average with the fewer gears so less work inside the transmission over 200,000 miles which again adds to the durability.