Re-gearing feedback from someone driving at higher elevation

[tnine]

Hi all,
I have a 2014 SR5. I'm considering adding ARB lockers and re-gearing. This is a pretty hefty price tag, around $5500 on average from several shops in time + material.


My 4Runner is very low mileage and still has a pretty high trade in value. I'm struggling with the decision to keep it and re-gear, or trade it in for a truck with a rear locker and a lower tow gear ratio + turbocharged engine. Some info about my driving conditions.


I've added quite a bit of weight. I have a Gobi Roof Rack, Rocky Road Steel Sliders, and a Bud Built undercover winch + warn M8000.


I drive at 6k feet of elevation up to 12k feet. My 4Runner really struggles at 6k and up to produce any torque with the NA engine. I have to really rev it up and downshift to get any power.


I have 32.7" tires. (255/80/17). I like the height, but the narrower tire gives me less rolling resistance. I'd prefer to to with 285/70/17 on my next set after a re-gear.



I'm considering going to something like a 4.88 ratio. I'm concerned that a 4.56 won't give me the torque I'm looking for. I'm trying to balance that with decent highway drivability. Has anyone that operates a 4runner at higher elevations re-geared? If so, did it give you the torque you're looking for?

Lastly, what gears did you use? A couple shops are recommending Nitto gears, but tell me they create quite a bit of noise at highway speeds.

I've read several forum posts, but they don't take into account operational altitude. When I visit the family in Indiana I have significantly more power than when I'm in Colorado, so feedback from people driving at higher altitudes is what I'm looking for.


Thanks in advance!
Todd

 

[Gtadiell]

Did you ever go through with this? I’m in the exact same boat. Love the car but hate driving it above 6-7k alt.

 

[Engineer]

Did you ever go through with this? I’m in the exact same boat. Love the car but hate driving it above 6-7k alt.

I won't be able to help you with driving at 6-7k but I do have 4.56s on order from East Coast gear supply so hopefully within 3-6weeks I can give you an answer. It does seem pretty universal that no one regrets regearing but since its a high cost I think those that go for it, know what they want are are happy with the results.

For me even though we are 600ft above sea level the real driver is highway driving with the extra weight, tires and general drag its a real bear to drive on the highway - I don't expect it to drive like a caddy, and the power is there, its just higher in the RPM band but after driving aJL rubicon for a week I was shocked at how well it drove on the highway compared to the 4runner - mainly in the power department but have a few extra gears in the transmission seems to be invaluable to keeping the engine in a nice power band.

 

[2021nightshade4x4]

Sort of relevant… does shifting into S adjust shift points at all, or ONLY let you set the top of the gear range?


Sent from my iPhone using Tapatalk

 

[jp.vegas]

Sort of relevant… does shifting into S adjust shift points at all, or ONLY let you set the top of the gear range?


Sent from my iPhone using Tapatalk

Only the top of the gear range. No change in shifting.

 

[sierrahiker]

I live at 2K and do a lot of mountain driving at 5K-10K ft (plus freeway/city driving pulling utility trailer down to sea level). My 2013 TE has sliders (steel), full skids (aluminum), Sherpa rack (aluminum), Bud Built hidden winch mount, Warn Zeon 10S, and 285/70/17 tires on 8.5" wheels. After adding the armor and switching to 285s, my 4runner was struggling a bit on steeper grades, particularly when carrying a full load of kayaking and camping gear. I pretty much stayed in 4S on the hills. I decided to re-gear to 4.56 (Nitro gears) and added ARB front lockers at the same time (TE comes with rear e-lockers). I've been very happy with the result and would do it again. Took a bit of hit on mpg, but the improvement in torque and driving experience, both on and off road, has been worth it to me. No issues (so far) with the Nitro gears or ARB lockers.

I have no complaints with the performance at higher elevations, but I don't do extreme crawling; your own satisfaction will obviously be influenced by how and where you drive, i.e., how much torque you need/want. I'm happy with the result, but the 4runner is never going to be a muscle truck no matter what you do to it. The shop where I had mine re-geared said that most guys who re-gear in this area go to 4.88 to maximize torque for rough terrain, but recommended 4.56 if my expected use included much freeway driving. Since I do considerable freeway driving, I took the shop recommendation and went with 4.56. That was a good choice for me; I don't think I would want 4.88 for freeway driving.

 

[TEujunga]

Sort of relevant… does shifting into S adjust shift points at all, or ONLY let you set the top of the gear range?

"S" mode can adjust shift points a little bit, depending on how you drive.

In "D" mode, AI-SHIFT function is enabled. Computer logic adjusts shifting behavior to match what it thinks is your driving style.

In "S" mode, AI-SHIFT is disabled and shifting behavior isn't affected.

For drivers with a habitual light foot, the trans may be quicker to engage higher gears in "D" than it is in "S" mode, and be more reluctant to downshift.

For drivers with a heavy foot, the trans may hold lower gears longer in "D" mode than in "S" mode.

 

[Jetboy]

Hi all,
I have a 2014 SR5. I'm considering adding ARB lockers and re-gearing. This is a pretty hefty price tag, around $5500 on average from several shops in time + material.


My 4Runner is very low mileage and still has a pretty high trade in value. I'm struggling with the decision to keep it and re-gear, or trade it in for a truck with a rear locker and a lower tow gear ratio + turbocharged engine. Some info about my driving conditions.


I've added quite a bit of weight. I have a Gobi Roof Rack, Rocky Road Steel Sliders, and a Bud Built undercover winch + warn M8000.


I drive at 6k feet of elevation up to 12k feet. My 4Runner really struggles at 6k and up to produce any torque with the NA engine. I have to really rev it up and downshift to get any power.


I have 32.7" tires. (255/80/17). I like the height, but the narrower tire gives me less rolling resistance. I'd prefer to to with 285/70/17 on my next set after a re-gear.



I'm considering going to something like a 4.88 ratio. I'm concerned that a 4.56 won't give me the torque I'm looking for. I'm trying to balance that with decent highway drivability. Has anyone that operates a 4runner at higher elevations re-geared? If so, did it give you the torque you're looking for?
I live at around 5500 feet and used to drive 3x per week to about 8500 feet. I regeared to 4.56 and then went back to 3.73. I found that I got significantly better highway mpg with 3.73 despite having 34" (285/75/17 E rated tires) and I also got better mpg towing my camper with 3.73 gears. The fuel consumption tells me that the engine is working harder with 4.56 diffs at highway speeds and/or is outside of the thermal efficiency range where it achieves the best efficiency. It did feel a LOT better around town and on the trails with 4.56 gearing. It REALLY needs a 6 speed so you can run 4.56 diffs and still have that higher OD gear. That would best the best all around solution.

I setup my own gearsets and kept the original 3.73, so swapping back and forth for me costs only a little bit for new gear oil and a saturday in my garage. And if you can DIY your gear swaps you're into it for about $1k for a low mile front and rear diff, $400ish for the two R&P sets, and about $100 each side for setup kits. I also replaced the pinion bearings on the rear with new for maybe $150. So I was a lot cheaper into it than going to a shop. It didn't hurt so bad to swap back to 3.73. If I hadn't kept my diffs and just used the originals, I'd only be into it about $800 for parts and my time to swap over. But if you haven't setup an 8" clamshell before - it's not a good place to learn. It's an absolute bear of a diff to set the pinion depth properly without the $$$ specialty depth tools that can measure pinion depth from the manufacturer's pinion markings rather than doing it by paint pattern.

If you want to know what 4.56 gears will feel like - drive in S4 on the highway. That's basically what 4.56 will be in 5th gear. Or close enough to get the idea. 4.56 does feel a lot peppier from a stoplight. It's night and day really as far as local driving goes. If I were doing mostly local driving and offroad miles I'd keep the lower gears. My life lately (kids...) is more road trips and towing the camper - so I went to 4.30 diffs in a tundra for a while.

Lastly, what gears did you use? A couple shops are recommending Nitto gears, but tell me they create quite a bit of noise at highway speeds.
I used Revolution gears. I believe all 8.2 diff gears are from Circle K in Korea, possibly even including OEM toyota gears, but I'm not totally sure if Toyota outsources them. If you buy them from Nitro - they're circle K in a nitro box. If you buy Revolution - circle K in a Revolution box. You get the idea. A gear set costs about $70-80 from the manufacturer. You can do the math on the markup. Buy whatever box gives you warm fuzzy feelings, or buy the cheapest ones you find and get the same thing in a different color box. Your choice on that.

I've read several forum posts, but they don't take into account operational altitude. When I visit the family in Indiana I have significantly more power than when I'm in Colorado, so feedback from people driving at higher altitudes is what I'm looking for.


Thanks in advance!
Todd

Good luck on finding the right fit for you! I think it may be worth taking a hard look at a supercharger instead. It's not a lot more $ if you're at $5500 for the shop to swap them out, but also goes a lot further toward fixing the elevation problem. Also FWIW - $5500 is a LOT for a diff swap. You can buy pre-built ECGS diffs for about $2k for the pair and a shop should be about 4 hrs of labor for each end. So it should be something more like $3k-3500 for the gear change.

 

[bayaz]

Good luck on finding the right fit for you! I think it may be worth taking a hard look at a supercharger instead. It's not a lot more $ if you're at $5500 for the shop to swap them out, but also goes a lot further toward fixing the elevation problem. Also FWIW - $5500 is a LOT for a diff swap. You can buy pre-built ECGS diffs for about $2k for the pair and a shop should be about 4 hrs of labor for each end. So it should be something more like $3k-3500 for the gear change.

He also said he’s getting a locker which is $1k-$1.5k. Also sounds like Utah’s cheaper than other places. In CA, regear labor is $2k.

 

[Gtadiell]

Can I ask what rpm you turn at 80. I’ve researched a ton of charts but frankly the more you look the more you question what it would actually be.

 

[Gtadiell]

I live at 2K and do a lot of mountain driving at 5K-10K ft (plus freeway/city driving pulling utility trailer down to sea level). My 2013 TE has sliders (steel), full skids (aluminum), Sherpa rack (aluminum), Bud Built hidden winch mount, Warn Zeon 10S, and 285/70/17 tires on 8.5" wheels. After adding the armor and switching to 285s, my 4runner was struggling a bit on steeper grades, particularly when carrying a full load of kayaking and camping gear. I pretty much stayed in 4S on the hills. I decided to re-gear to 4.56 (Nitro gears) and added ARB front lockers at the same time (TE comes with rear e-lockers). I've been very happy with the result and would do it again. Took a bit of hit on mpg, but the improvement in torque and driving experience, both on and off road, has been worth it to me. No issues (so far) with the Nitro gears or ARB lockers.

I have no complaints with the performance at higher elevations, but I don't do extreme crawling; your own satisfaction will obviously be influenced by how and where you drive, i.e., how much torque you need/want. I'm happy with the result, but the 4runner is never going to be a muscle truck no matter what you do to it. The shop where I had mine re-geared said that most guys who re-gear in this area go to 4.88 to maximize torque for rough terrain, but recommended 4.56 if my expected use included much freeway driving. Since I do considerable freeway driving, I took the shop recommendation and went with 4.56. That was a good choice for me; I don't think I would want 4.88 for freeway driving.

Can I ask what rpm you turn at 80. I’ve researched a ton of charts but frankly the more you look the more you question what it would actually be.

 

[Nalcyon]

Just some more food for thought for those researching a re gear...

I have regeared several vehicles in the past, (1967 Camaro, 04 mustang GT, 08 JK, current 4runner), and agree that no mod effects the drivability more per dollar than a re gear. But be sure you are clear on what you are trying to accomplish.

The [typical] weight added to our 4runners is a factor in drivability but with the stock 3.73 gears is manageable. The bigger issue is when you change to a larger tire size. Weight + larger tires= a noticeable hit in drivability.

Without getting into the physics for what we are doing with our 4runners gears may help with acceleration on the road but that is not the primary goal. The primary goal of regearing for most of us is to increase mechanical advantage so that our driveline is under less stress, like using a bigger lever on a jack so that you don't have to work as hard to move it.

I went with 4.56 gears to accomodate my tire size and mods, (285's gobi rack, sliders, SSO winch bumper, C4 rear bumper), and am pretty happy with the results. For the way I use the 4runner it is a big improvement over stock when driving down the road.

OFFROAD: 4.56 gears with 285's will get you to about the stock crawl ratio which is still too fast for my liking. The main issue is the 4runner has a fairly tall 1st gear and it shows offroad. That said it is perfectly adequate for what I do.

ONROAD: It feels like it did stock as far as shifting, acceleration, gear holding etc. Once again the gear ratios of the transmission leave more to be desired than the final drive ratio.

A CAVEAT: Even before re gearing I limit my top speed to about 60mph unless on the interstate where I go 65. This is not because of the motor having to strain, but just because of the amount of weight I carry and the removal of the sway bars, I don't want to have to make an emergency maneuver at high speeds with this 4runner. I still average 15mpg and can get close to 17 when on the highway in relatively flat terrain. At 60-65 5th gear is held for most highway driving only downshifting on fairly steep grades.

This is better than I was getting with the same setup but stock gearing. It is a misconception that raising the gear ratio always kills your mileage. It depends on how you're driving, where you're driving, and the transmission. Out of the 4 vehicles I have regeared the JK, (3.21 to 4.88 with a six speed manual), and the 4runner (3.73 to 4.56 with 5 spd auto), have improved their mpg while the camaro, (2.76 to 3.73 with 4spd manual), and 04 Gt, (don't remember to 4.10 with 5speed manual), hurt mpgs.

A caveat of a caveat: While the JK did increase mileage overall, if driving straight highway the mileage was indeed down a little.

I realize I'm rambling. Let me know if you have any specific questions.

 

[comtn4x4]

Just some more food for thought for those researching a re gear...

I have regeared several vehicles in the past, (1967 Camaro, 04 mustang GT, 08 JK, current 4runner), and agree that no mod effects the drivability more per dollar than a re gear. But be sure you are clear on what you are trying to accomplish.

The [typical] weight added to our 4runners is a factor in drivability but with the stock 3.73 gears is manageable. The bigger issue is when you change to a larger tire size. Weight + larger tires= a noticeable hit in drivability.

Without getting into the physics for what we are doing with our 4runners gears may help with acceleration on the road but that is not the primary goal. The primary goal of regearing for most of us is to increase mechanical advantage so that our driveline is under less stress, like using a bigger lever on a jack so that you don't have to work as hard to move it.

I went with 4.56 gears to accomodate my tire size and mods, (285's gobi rack, sliders, SSO winch bumper, C4 rear bumper), and am pretty happy with the results. For the way I use the 4runner it is a big improvement over stock when driving down the road.

OFFROAD: 4.56 gears with 285's will get you to about the stock crawl ratio which is still too fast for my liking. The main issue is the 4runner has a fairly tall 1st gear and it shows offroad. That said it is perfectly adequate for what I do.

ONROAD: It feels like it did stock as far as shifting, acceleration, gear holding etc. Once again the gear ratios of the transmission leave more to be desired than the final drive ratio.

A CAVEAT: Even before re gearing I limit my top speed to about 60mph unless on the interstate where I go 65. This is not because of the motor having to strain, but just because of the amount of weight I carry and the removal of the sway bars, I don't want to have to make an emergency maneuver at high speeds with this 4runner. I still average 15mpg and can get close to 17 when on the highway in relatively flat terrain. At 60-65 5th gear is held for most highway driving only downshifting on fairly steep grades.

This is better than I was getting with the same setup but stock gearing. It is a misconception that raising the gear ratio always kills your mileage. It depends on how you're driving, where you're driving, and the transmission. Out of the 4 vehicles I have regeared the JK, (3.21 to 4.88 with a six speed manual), and the 4runner (3.73 to 4.56 with 5 spd auto), have improved their mpg while the camaro, (2.76 to 3.73 with 4spd manual), and 04 Gt, (don't remember to 4.10 with 5speed manual), hurt mpgs.

A caveat of a caveat: While the JK did increase mileage overall, if driving straight highway the mileage was indeed down a little.

I realize I'm rambling. Let me know if you have any specific questions.

I think this is all spot on. The only thing I'd add goes back to the [MENTION=118321]Jetboy[/MENTION] post. If you want more power a supercharger is really the answer. Or ideally both a re gear and a supercharger.

I've been getting a number of messages lately asking about re gearing at altitude and will it make the 4Runner on 33's do 75 mph up I70 west of Denver without hunting for gears or feeling under powered? The answer really is no it won't. It'll make it better for sure.

I wanted to give this example I haven't seen provided about driving at altitude, Colorado in particular. I've read that every 1000 feet above sea level robs an engine of 3% of it's power. So assuming that's true, around Denver for our 270 HP 4Runners the effective horsepower would be about 224 which is a reduction of about 17%. In Breckenridge it'd be 199 HP and a reduction of 24%. At the top of Pikes Peak 176 HP and a reduction of 45%. So that being said a re gear isn't going to fix this obviously, nor is mashing the skinny pedal. But as [MENTION=552135]Nalcyon[/MENTION] said it does help balance the big tires and extra weight we tend to add to our rigs. And all the jeeps on 37's can't even keep up with us anyway. (Unless they have a 392) Most groups I've been with going up I70 average 55-60 mph at best.

All that being said I still love my 4:56 gears after 70,000 miles and I'd totally do it again.

 

[Grug556]

If your high up... forced induction is the way forward. Either supercharger or turbo. Likely more effective than re gearing using a supercharger instead.

 

[Jetboy]

I ended up solving my problem by adding two cylinders and 4.30 gears.

But I really miss my 4runner. It was just a lot more enjoyable to drive. And vastly more capable off-road in the places I tend to go. The truck is just so big and heavy and hard to get around anything tight. I can't imagine trying the more technical stuff.

 

[fkheath]

If your high up... forced induction is the way forward. Either supercharger or turbo. Likely more effective than re gearing using a supercharger instead.

Agreed. It sounds to me that the concern is highway (paved) driving at altitude. Yes, the 4Runner is a bit short of power. Re-gearing just raises the RPM in any given gear, but you can do that by down shifting using the S mode anyway.

My example is Colorado highway 62 over Dallas Divide -- quite steep paved road at 8K to 9K elevation. I do that every summer towing a utility trailer with my ATV, and lots of supplies too. Only solution is to downshift and take it slow and easy rather than storming up the hill. More power (forced induction) would help there.

But for off roading at high elevation, that is what 4Lo is for. My examples then would be Imogene, Cinnamon, and Engineer passes in western Colorado (13K + elevation). I have never run out of power on any of them with stock gearing on my SR5 with a full load of passenger in my three row 4Runner.

 

[sierrahiker]

Can I ask what rpm you turn at 80. I’ve researched a ton of charts but frankly the more you look the more you question what it would actually be.

Approximate rpm values with 4.56 gearing and 285/70/17 tires:

60mph: 2080 rpm
70mph: 2430 rpm
80mph: 2780 rpm

Testing performed on flat terrain. RPM measured using ScanGuage. Speed set using gps and held at specified value using cruise control.

 

[FoxtrotRomeo]

How about this link: Calculate RPM for Given Speed(MPH), Rear Gear Ratio, and Trans Gear Ratio

Do these numbers make sense?

 

[Gtadiell]

I did go through with regear. I went 4.88 at the recommendation of the shop. Also added an air locker in the front. Still doing the break in but my initial reaction is that I should’ve done this much sooner. It just feels like the 4runner isn’t working as hard. In Denver on 285/70/17’s I turn about 2200 at 60 and 2500 at 70. I’m not expecting to hold 5th climbing vail pass, but hopefully it’ll just shift down to 4th and maintain vs dropping into 3rd and screaming.