Folks with 32's, autos, and 4.10s step in

[cashmoney]

Are y'alls vehicles constantly gear hunting and down shifting at highway speeds on any hint of a hill? I'm talking 55+mph.

 

[BrianSD_42]

What kind of tires (type, load rating)?

How much weight have you added? (sliders, bumpers, skids, winch etc)

What altitude do you live at?

My truck feels about 40HP stronger at sea level than it does at 7500 ft.

 

[cashmoney]

I'm a touch above sea level but not enough to matter. No armor. Tires are in my sig. 265/75/16 nitto terra grapplers. Believe they are the D range rating can't remember right now. I do know they are the LT and not P.

 

[MxwlT4R99]

I have this exact setup as well. I experience the exact same things you describe when any sort of hill is involved, and it leads to some major momentum/power loss if I don't keep at the gas.

I go to school in Missoula, MT, and drove to Seattle this last spring. When I was going over the pass, it gear hunted pretty much the whole time. For a portion of the trip my foot was nearly to floor...

 

[A.Wilson013]

I had this same problem even with the supercharger until I pressed that little "ECT" button. That thing is a God send.

For the BIG hills turn off your OD and it'll charge right up.

With bigger tires, armor, and SC I still have this issue when I am going 65.... I think it's just a strange spot in the RPM range. 60 or 70 I am fine, but at 65 it wants to shift all the time.

 

[absalom]

I have the exact setup and mine does this when cruise control is on. It was MUCH worse when I had 33's on though. I can't stand the tranny downshifting on it's own, it's a major motivation for my swap. I loathe automatic transmissions.

 

[JayRolla]

Im running 4.10's, 33x12" D load. Front bumper, lift, winch with wire and I drive just fine in the city. Going up the passes here in CO I do get the issue you have, doesnt want to stay in a gear, searching all the time. Sometimes I will shut OD off which helps. Ive learned to get momentum up those hills and drive around the issue. I was planning on regearing one day but so far its not in the budget. I can live with it. She picks up and goes fine just sometimes that pass can be a little rough when loaded down.

 

[jgue467]

I'll be the one to break the 32 rule, got 31s and won't use cruise cuz almost any gentle hill will cause it to downshift rudely into a lower gear then not want to upshift anytime soon. No cruise = perfection. :cowboy:

 

[OU4x4]

factory 4.10, with 285s, lift, front bumper, winch, sliders, and roof rack
just whisper the word "hill" and she freaks out.
and living at altitude doesn't help
turning off over drive solves the problem but the mpgs suck.
i might have the wife talked into a SC!!

 

[cashmoney]

So it sounds like there really isn't a problem with my 4runner and it's just normal for it to down shift constantly and gear hunt with larger tires. I absolutely loathe down shifting and gear hunting and not being able to maintain speed up hills. I'll start hunting for some 4.88's. That should suit me nicely especially once I put bumpers and skids on.

 

[Vannnce]

Ours will usually unlock the converter on little hills, and downshift on the bigger ones. Like others have said though, this is only with the cruise control on. Without cruise on i can stay in overdrive pretty easily. I also run with the ect or whatever it is on

 

[xcmtb83]

I used to have 32" tires and 4.10 gearing if that answers your question.

 

[cashmoney]

Cruise on or off and ect on or off makes no difference.

 

[StreetCreeper]

Same setup I have and while I'm not exactly climbing the Rocky Mountains out here on the west coast, I do my fair share of mountain driving. I run 100% of the time with the ECT button on and when I'm in hill country, I don't use the cruise control. I also use the OD button anytime I hit a hill and the vehicle starts to slow. Instead of giving it more gas—I give it better gearing.

I have no issues going up hills/mountains around here, even when fully loaded. My fuel mileage on a recent 1200 mile trip through about 70% hill/mountain country was about 19.5 mpg average—fully loaded with A/C cranked up.

Nothing passed me on the hills either. I have no problems maintaining 65-70 on the passes with my RPMs around 3—3.5k. I'm sure this would change climbing the Rockys at high altitude though.

****EDIT**** Just went and looked up the axle code again and realized I have 4.30 ratio instead of 4.10. Guess that makes a difference eh...

 

[cashmoney]

I used to have 32" tires and 4.10 gearing if that answers your question.

Not really because I don't know what you changed to after that.

 

[xcmtb83]

Going down to stock 31" P rated tires and swapping in a 4.30 was enough to help.

 

[1985taylor1925]

I have all the same issues everyone has already mentioned. 32" tires, auto and 4:10 gears. Cruising down the highway the engine just doesn't make enough power at the lower rpms with the increased tire size. Im at just under 1000ft in elevation here in WI. Mine will downshift on hills, or if there's a strong enough headwind, so I rarely use my cruise any more. When I make the drive from Wisconsin to Wyoming where my family lives, its a miserable endeavor. Part way through Nebraska you start climbing in elevation. That combined with hurricane Nebraska winds will frequently push my truck into 3rd gear while in cruise. I finally learned its just better not to use it driving through NE. I learned I could keep it close to 75 while staying in 5th gear if I used the pedal correctly.

Anyone here switched from 4:10s to 4:30s while running 32" tires? I have a set of 4:30s in my garage ready to install when I get a chance. Im wondering how big of a difference it will make?

 

[cashmoney]

I'm going to jump to 4.56-4.88. 4.30s aren't enough to justify the difference to me especially since I plan on jumping to 33" tires next time I need new ones.

I've learned to just leave OD off. Engine screams but I'm knocking down 15.8mpg so meh.

 

[98OzarksRunner]

So it sounds like there really isn't a problem with my 4runner and it's just normal for it to down shift constantly and gear hunt with larger tires. I absolutely loathe down shifting and gear hunting and not being able to maintain speed up hills. I'll start hunting for some 4.88's. That should suit me nicely especially once I put bumpers and skids on.

It's normal with smaller tires, and probably with lower gears too. 4.88s might help some but it'll still downshift on steep hills, as well as kill the already terrible mileage. My 3rd gen with 32s and 4.10 gears does pretty well (I had a 2nd gen that wouldn't hold speed on a long, steep hill - at least the 3rd gen holds speed even if it does downshift). But, I have a stock GX470 with the V8 and it downshifts on long, steep hills. That's just the nature of trying to lug a heavy vehicle uphill. It might get better with 4.88s but it's not going to keep it from downshifting. If you want to hold speed without downshifting, buy a Mustang GT or a Camaro SS (or a Corvette). More power and less weight and wind resistance. My wife's 06 Mustang GT could climb about any hill in 5th gear without losing speed. You're not likely to get that out of a 3rd gen, even with 4.88s and a supercharger. I have a 3rd gen because it will go anywhere, not because it will go fast.:happy:

 

[cashmoney]

I've got a 350z (see sig) for speed (getting long tubes and a rear mount turbo). I can see it being normal on large hills but I'm talking on flat ground or even the slightest little hill it'll downshift. That can be rectified with 4.88's (and a turbo). I've had diesels that would downshift on large enough hills and those have more torque off idle than we could dream of with these things.

Right now I'm getting 15.8mpg in 3rd gear at 80mph hand calculated. I can't imagine 4.88s in OD being worse.