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steve103
01-08-2012, 06:46 PM
any one have 255/85/16 tires and manual trany. if any problems with shifting to 5th with out regearing. 07 tacoma v6 4x4

Applejack
01-08-2012, 07:02 PM
Which vehicle would this be?

steve103
01-08-2012, 07:17 PM
just because i know i guess not eveyone else does,duh. sorry. 07 tacoma v6 4x4.

Rocket-scientist
01-08-2012, 07:54 PM
I'm running that combo. I have the six speed and only need to down shift when going up long steep grades. Around town I've lost 1 MPG but gained 1 on the highway at 70 MPH. I would imagine the 5 speed would be similar. I love these tires BTW!

steve103
01-09-2012, 12:59 AM
what about off road,snow sand rock mud?

Rocket-scientist
01-09-2012, 02:32 AM
what about off road,snow sand rock mud?

Off road, in 4 low, it's fine. No issues so far. Once again it's a loss of power, but not that bad. I haven't found a time yet where I need more power.

downhill
01-09-2012, 05:57 AM
I really disliked the 3.73 gears and swaped them out for 4.56. IMO any increase in tire size just makes a bad situation worse. I'm running a 32" tire which is shorter than the 255, but I like the new gearing much better. It is more in line with what I use a truck for. If you plan on adding weight to the truck I think the gearing may become more of an issue. It all depends on what you want though. My truck is an 07 6spd access cab. I use it for long distance travel, towing, hauling gear.

Applejack
01-09-2012, 11:53 AM
I wouldn't imagine you having any problems at all. I'm not sure what specific tire you want to run but for example, a BFG KM2 in the 265/75 size is 53lbs and the same tire in a 255/85 is only 2lbs heavier weighing in at 55lbs, or so says Tire Rack.
If you are stepping up from the stock tires though, I'm sure you are going to notice the power loss but still have the guts to move them.

steve103
01-10-2012, 04:55 PM
i thought that the 07 acc cab v6 4x4 has 410 gears,am i wrong?

downhill
01-11-2012, 03:49 AM
i thought that the 07 acc cab v6 4x4 has 410 gears,am i wrong?

Nope, they come with 3.73. The 4.56 gears are a tad low for my tires on the road, but IMO would be perfect for the 255s. Mostly my highway driving is 65 or less, so no worries for me. Offroad the difference was dramatic. I've actually got a crawl gear now that I can use for some technical work. The stock gearing works for things that require maintaining speed like sand and mud. I don't do any serious rock crawling with this truck, but sometimes you need to pick your way over something and that is where the gears make a big difference. Reverse gear in these trucks is too tall as well, and the lower gears improved that. With the 32s and 4.56 gears I lost about 1.5 MPG on the highway. With 255s you would probably lose less (if any). The 4.0 is turning faster but is operating farther up the torque curve. It's pretty flat at 2000 or less. At 2400-2500 it starts to come alive. I rarely have to downshift on hills unless I'm towing or hauling.

One more thing to consider. Toyota used a crush spacer in the pinion gear to make factory set-up faster. Under normal loads the pinion doesn't see enough pressure to further crush the spacer and alter the gear mesh. If you go to a tall tire and get too excited offroad, you could cause that to happen. When I replaced my gears I installed solid spacers, like most diffs run to prevent the problem.

You may not need gears for mild adventuring, that's your call. These are just things I've experienced for reference.

mvbeggs
01-11-2012, 01:06 PM
I've been discussing this same issue over in TACODOC's 2005 Tacoma build thread. Here's some numbers I posted over there regarding gearing, tire size. Most of these numbers were calculated for the auto tranny, but may have some relevance here.

These numbers led me to think that 4.10 is the correct gearing for me. I want/need my max cruise to be about 85mph without the engine screaming down the highway. (No heavy crawling, ability to pull the AT Chaser trailer, and probably nothing more than a 4 rated trail.)

8136481365

I couldn't find a dyno curve specific to the Tacoma, but this is one from an FJ with the same engine. I'm assuming this discussion is about the 4.0L.
81366

downhill
01-11-2012, 02:37 PM
MVbeggs,
That's a great reference. Look at the difference in torque from 2000 to 2500. That is why I set mine up for cruising around 2400-2500 most of the time. Of course that was assuming a lower cruise speed and a manual gear box. I do alot of towing with a 2500 lb trailer, and I can tell you it makes a huge difference staying in that range. Typically, when I tow I also have 300-400 pounds of gear in the truck as well, and I lose 2 to 2.5 MPG which includes lots of grades. If you have a stock truck running mostly empty, you can afford the lower rpm and lower torque, but loaded you end up in a lower gear anyway on any incline. Heavier tires are also part of the load.

Regarding gear selection, last time I checked nobody offers an aftermarket gear set in 4.10. It is Toyota only and very expensive. I think it is really unfortunate that nobody offers 4.30. That would put alot of people right with the world that are not going to extremes. I would have chosen 4.30 if it were offered.

just reading off that graph:
At 2000 RPM = roughly 85 ft/lbs = 23.5 RPM per ft/lb
at 2500 RPM = roughly 185 ft/lbs = 13.5 RPM per ft/lb
More than double the torque for just 500 RPM is a pretty good bargain.

I think Doc's gearing is spot on.

keating
01-12-2012, 03:44 AM
I've got a stock V6/Auto with the stock 245/75R16 Dunlop tires and the thing feels like it could use more gear. I'm going to 265s, since they're stock size on the TRDs it should be deemed "acceptable", but I'm dreading it. I can't imagine running 255/85R16 on 3.73s. For anyone who doesn't have the TRD OffRoad with E-Locker, wouldn't you have the 8" front and 8.4" rear, same as a 4 banger? There should be some 4 banger 3rd-members with 4.10s in junkyards by now?

mvbeggs
01-12-2012, 04:00 AM
... Look at the difference in torque from 2000 to 2500. That is why I set mine up for cruising around 2400-2500 most of the time.... I do alot of towing with a 2500 lb trailer, and I can tell you it makes a huge difference staying in that range. Typically, when I tow I also have 300-400 pounds of gear in the truck as well, and I lose 2 to 2.5 MPG which includes lots of grades. If you have a stock truck running mostly empty, you can afford the lower rpm and lower torque, but loaded you end up in a lower gear anyway on any incline. Heavier tires are also part of the load....

Regarding gear selection, last time I checked nobody offers an aftermarket gear set in 4.10. It is Toyota only and very expensive. I think it is really unfortunate that nobody offers 4.30. That would put alot of people right with the world that are not going to extremes. I would have chosen 4.30 if it were offered......

Downhill,

Thanks for the response.

Have to agree with about everything you say. The 4.0L just doesn't have a lot of low end torque. Also agree with what you said about the 4.30 gears. I'm looking pretty seriously at a Tacoma build for the trips I don't need the rock crawling abilities of the Jeep. (mostly the hunting trips) I believe there is someone now offering a 4.10 ring and pinion set for the Taco.

I'm really interested in the experiences folks have had pulling trailers. (I'll be pulling my Chaser on most trips) I worry very little about the Tacoma's performance when lightly loaded. I'm not so sure how it will perform when loaded and pulling a trailer. I'm sure lower gearing would make towing a "non issue". My fear is that the low gearing will make her a bit obnoxious as a daily driver on the highway. (i.e. high rpms at 70mph-85mph) Compromises, compromises, compromises. :-(

What kinds of grades do you drive? Do you ever drive in Colorado, on I-70, up to the Eisenhower Tunnel? (that's a pretty good grade if you're not familiar with it) I'd be interested, if anyone would care to share, what kind of engine rpms are required to pull a 2,500lb trailer at 65mph up a similar grade.

Also, what are you driving auto or manual, what tires are you running, and how are you currently geared?

downhill
01-12-2012, 08:55 AM
Mvbeggs,
I spend half the year or more traveling, mostly the western states. I'm familiar with virtually all the rocky mountain grades. My trailer weighs 2350 on the axle with 225 on the tongue for a combined truck load of around 600 pounds with gear. I have the 4.56 gears with 235/85-16 E rated tires (approx 32"). My unloaded truck weight is 5350 with a full tank, me and 2 dogs. I also towed this combination with stock gears prior to the switch. At 65 I'm turning 2550 RPM in high gear (manual 6 spd). With the 255s you would need the 4.88 gears to approximately match what I have.

With regards to daily driving: I love the lower gears around town. The only downside was that they produced even more axle wrap than I had with the 3.73. That was eliminated with the installation of All-Pro expedition springs.

With regards to highway driving: The 4.0 does not produce much power below 2400, but the good news is that the engine purrs right along at the higher speeds. My highway speeds are never above 70 and usually around 65. That keeps me under 3000 RPM.


With regards to towing: While the 3.73 gears did work, I found the 4.56 much more enjoyable to drive. Launching and accellerating through the gears is much easier, especially loaded on a hill. Down the road the difference is about one gear. With the 3.73 I would be one gear lower for the same incline than I would be with 4.56. Moderate grades require no downshift. I just lean into the gas a bit and it rolls on. Steeper grades like the I70 climb, the Siskyou pass etc, I take in 5th gear running I think around 2850 RPM. The only climbs that get me into 4th and down to 55 are like the climb into the Tetons out of Jackson Hole. On alot of these passes altitude also takes it's toll, but I can't recall ever hitting 3rd unless for traffic or corners.

There is one issue though that is probably not common knowledge. The weak link in the towing ability of the 4.0s is the rear diff. Both the 8" and the so called
"8.4" measure 8". That is a really marginal gear size for the power of the 4.0 under high loads. When I swapped gears after just 20K of combined towing my carrier bearings were already showing evidence of spinning. To monitor the situation I installed a temperature probe in the rear diff during the gear change. My typical unloaded diff temp running mostly flat or rolling hills is between 125 and 165 degrees. The same run with the trailer and weight runs 150 to 185. When I start climbing hard the heat builds fast and often runs 200 to 220 degrees. I don't let the temp ever exceed 225 degrees. If I approach that I get a lower gear and slow down. Above 225 the rate of viscosity breakdown accelerates and at 250 it is cooking the oil. The point is, the truck has the power to cook the diff under these conditions and I would never know it without the gauge. No doubt I had done that before the gear swap which resulted in the spun bearings. I would advise anyone towing under similar conditions to take it easy up steep sustained grades, especialy in the summer. I change my rear diff oil every year and I'm currently running Amsoil Severe Gear 75/140. At the last change out the oil looked just fine after running all over Wyoming, Montana, Idaho, Washington, Oregon, and Northern California. The trick is not overheating it. I could probably go longer on a fill, but I know the gears are working at their limit at times so I spend the bucks and change it out.

Hope that helps....

mvbeggs
01-12-2012, 01:43 PM
Mvbeggs,
I spend half the year or more traveling, mostly the western states. I'm familiar with virtually all the rocky mountain grades. My trailer weighs 2350 on the axle with 225 on the tongue for a combined truck load of around 600 pounds with gear. I have the 4.56 gears with 235/85-16 E rated tires (approx 32"). My unloaded truck weight is 5350 with a full tank, me and 2 dogs. I also towed this combination with stock gears prior to the switch. At 65 I'm turning 2550 RPM in high gear (manual 6 spd). With the 255s you would need the 4.88 gears to approximately match what I have....<snip>

Hope that helps....

That is EXACTLY the kind of information I need. Thank you for the in depth, response. Your entire response really gives me something to sink my teeth into.


....At 65 I'm turning 2550 RPM in high gear (manual 6 spd). With the 255s you would need the 4.88 gears to approximately match what I have....

I may have to live with some downshifting on the steep grades. (After gearing and tires, it looks like 4th gear in the auto, 1.00 tranny gear ratio, would put me at about 62mph at 2550 rpm.) I'm concerned the 4.56 or 4.88 gearing would kill me, and the gas mileage, coming across the flats of Kansas and Colorado at 80mph. What kind of gas mileage are you getting in your access cab? One of my main goals for a Tacoma build is to increase my range over the Jeep's.


....There is one issue though that is probably not common knowledge. The weak link in the towing ability of the 4.0s is the rear diff. Both the 8" and the so called "8.4" measure 8". That is a really marginal gear size for the power of the 4.0 under high loads. When I swapped gears after just 20K of combined towing my carrier bearings were already showing evidence of spinning....

Good to know. I wouldn't have thought that about the rear diff. Too bad they don't build the Tacoma as stout as they build the Tundra. Great intel on the operating temps in the rear diff. So, am I correct in guessing, you wouldn't recomend supercharging the 4.0 in fear of totally annihilating the rear diff? :ylsmoke:

downhill
01-12-2012, 04:43 PM
I may have to live with some downshifting on the steep grades. (After gearing and tires, it looks like 4th gear in the auto, 1.00 tranny gear ratio, would put me at about 62mph at 2550 rpm.) I'm concerned the 4.56 or 4.88 gearing would kill me, and the gas mileage, coming across the flats of Kansas and Colorado at 80mph. What kind of gas mileage are you getting in your access cab? One of my main goals for a Tacoma build is to increase my range over the Jeep's.



Good to know. I wouldn't have thought that about the rear diff. Too bad they don't build the Tacoma as stout as they build the Tundra. Great intel on the operating temps in the rear diff. So, am I correct in guessing, you wouldn't recomend supercharging the 4.0 in fear of totally annihilating the rear diff? :ylsmoke:

My stock gas mileage was 18 MPG. That was stock gears and close to the stock 4,000 weight. Now I'm getting 16 running empty with 1,000lbs additional weight. Add the trailer and gear and I'm down to about 13 in the mountains, 14 over rolling terrain. I very rarely ever see flat land, so I don't have good numbers for that.

Most manufactures size the diff according to power output and expected load. Toyota got it right for the smaller engines, but when they went to the 4.0 they did not upgrade the diff along with it. IMO that was a big mistake given the substantial increase in power. I think partly it was because they targeted this truck for urban use and figured they could get away with it. They were also trying to run up the MPG numbers for sales reasons. That's why they hobbled it with 3.73 gears too. That's all my conjecture of course, but I'll bet it's close. I've heard of these diffs being burned up with supercharged 3.4 engines towing on grades. If I saw the need to supercharge mine, I would include the cost of a Dana 60. Honestly though, I think the 4.0 is a fabulous engine for these trucks. If I really needed more I would probably just buy a bigger truck. The 8.0/8.4 rear end has proven surprisingly durable, I have to say. Understanding it's limitations and using a little care should help it live a long life. To be fair we are loading these trucks pretty good with all the armor and equipment.

mvbeggs
01-12-2012, 09:56 PM
My stock gas mileage was 18 MPG. That was stock gears and close to the stock 4,000 weight. Now I'm getting 16 running empty with 1,000lbs additional weight. Add the trailer and gear and I'm down to about 13 in the mountains, 14 over rolling terrain. ...

Most manufactures size the diff according to power output and expected load. Toyota got it right for the smaller engines, but when they went to the 4.0 they did not upgrade the diff along with it. ....

....I've heard of these diffs being burned up with supercharged 3.4 engines towing on grades. If I saw the need to supercharge mine, I would include the cost of a Dana 60. Honestly though, I think the 4.0 is a fabulous engine for these trucks. If I really needed more I would probably just buy a bigger truck....

Downhill,

Thanks so much for the straight forward answers. Your response has given me reason to pause. (manual-4.56 gears-armored-and skinny tires yields 13-14mpg pullng the trailer in the mountains...16mpg running empty) Maybe your suggestion of a larger vehicle should be considered...:confused:

When I started building the Jeep, I knew nothing of overlanding. I only knew that I was going to be in the back country, and on my own. I didn't want to be stranded, so I built a Jeep that is capable of going over very difficult obstacles without breaking anything. Well, mission accomplished...the only problem is that I have a very capable, 6,000+ lb, 11mpg, Jeep with about a 200 mile range. Too bad I didn't give more thought to range and gas mileage during that build. If realistically, a Taco build is to going to improve gas mileage from my current 11mpg to the 13-14mpg range, I probably need to keep looking for a setup that will get me into the 15-16mpg range.

Thanks for your unbiased, straight forward, comments. You gotta love the portal!

Hope to see you on the trail. A cold beer is in my cooler wating for you!:beer: Thanks again.

steve103
01-13-2012, 01:53 AM
mvbeggs thanks i think i would like to look at the 410s any good starting point?

steve103
01-13-2012, 01:55 AM
mvbeggs thanks i think i would like to look at the 410s any good starting point?

downhill
01-13-2012, 02:55 AM
Downhill,

Thanks so much for the straight forward answers. Your response has given me reason to pause. (manual-4.56 gears-armored-and skinny tires yields 13-14mpg pullng the trailer in the mountains...16mpg running empty) Maybe your suggestion of a larger vehicle should be considered...:confused:

When I started building the Jeep, I knew nothing of overlanding. I only knew that I was going to be in the back country, and on my own. I didn't want to be stranded, so I built a Jeep that is capable of going over very difficult obstacles without breaking anything. Well, mission accomplished...the only problem is that I have a very capable, 6,000+ lb, 11mpg, Jeep with about a 200 mile range. Too bad I didn't give more thought to range and gas mileage during that build. If realistically, a Taco build is to going to improve gas mileage from my current 11mpg to the 13-14mpg range, I probably need to keep looking for a setup that will get me into the 15-16mpg range.

Thanks for your unbiased, straight forward, comments. You gotta love the portal!

Hope to see you on the trail. A cold beer is in my cooler wating for you!:beer: Thanks again.

No problem, glad I could help!

mvbeggs
01-13-2012, 01:18 PM
mvbeggs thanks i think i would like to look at the 410s any good starting point?

Here's where I saw them:

http://www.nitro-gear.com/ring-pinions/

There are several parts that look like they will work:
TV6-411-NG TOY V6 4.11 R&P ALSO TACOMA & 4RUNNER W/LOCKER
T8S-410R-OE TOYOTA 8" CLAMSHELL 4.10 (OEM)(05+ TACO, FJC)


also saw this 4.30
TV6-430-NG TOY V6 4.30 R&P ALSO TACOMA & 4RUNNER W/LOCKER

Let us know if your verify that these WILL work in the '05 and newer Tacos.

downhill
01-13-2012, 04:29 PM
You need to email them. The website is deceptive. I'm pretty sure they only offer those gears for the rear and not the front, making them unusable in 4x4 applications.

mvbeggs
01-13-2012, 07:07 PM
Here's where I saw them: (Tacoma 4.10 R&P)

http://www.nitro-gear.com/ring-pinions/

There are several parts that look like they will work:
TV6-411-NG TOY V6 4.11 R&P ALSO TACOMA & 4RUNNER W/LOCKER
T8S-410R-OE TOYOTA 8" CLAMSHELL 4.10 (OEM)(05+ TACO, FJC)
.....


You need to email them. The website is deceptive. I'm pretty sure they only offer those gears for the rear and not the front, making them unusable in 4x4 applications.

Thanks Downhill. The link was from another discussion I was following. The extent of my due diligence was to click on the provided link to see the 4.10 listed. I didn't go any further with it.

Steve103, Please let us know if you verify the existence of the elusive Tacoma 4.10, front AND rear, ring and pinion sets.

steve103
01-15-2012, 01:23 AM
thanks every one for all your imput. new to all this so all the information is almost overwhelming. i will up date as time goes by. still need to get tires and see what happens. the 410 approach sound like what i would be looking for, 456 might be to much. we will see.

mvbeggs
01-15-2012, 01:25 PM
After giving it some thought, and more research, I traded the 08 Tundra (2wd) in on a 2012 Taco. (white, double cab, V6, TRD Off Road package) It should be in my hands this week.

The goal is to build a rig that will get 15-16mpg and able to tackle moderate trails. The approach will be to build in phases, and evaluate the gas mileage and performance after each mod. Planned mods: fiberglass bed topper, aluminum front bumper, winch, steel or aluminum rear bumper, sliders, suspension and tires (re-gearing if required).

Keep the posts flowing. I'm looking forward to learning more from everyone's mods and ideas.

Thanks for all the great input.

1911
01-15-2012, 03:02 PM
thanks every one for all your imput. new to all this so all the information is almost overwhelming. i will up date as time goes by. still need to get tires and see what happens. the 410 approach sound like what i would be looking for, 456 might be to much. we will see.

From my experience (with other trucks, including the FJC but NOT the Tacoma), going from 3.73 to 4.10 is barely noticeable, only a 10-11% difference. A lot of money to re-gear, for that little of difference IMO.

downhill
01-15-2012, 04:25 PM
After giving it some thought, and more research, I traded the 08 Tundra (2wd) in on a 2012 Taco. (white, double cab, V6, TRD Off Road package) It should be in my hands this week.

The goal is to build a rig that will get 15-16mpg and able to tackle moderate trails. The approach will be to build in phases, and evaluate the gas mileage and performance after each mod. Planned mods: fiberglass bed topper, aluminum front bumper, winch, steel or aluminum rear bumper, sliders, suspension and tires (re-gearing if required).

Keep the posts flowing. I'm looking forward to learning more from everyone's mods and ideas.

Thanks for all the great input.

Hey congratulations! stick or auto? My advice would be to keep it light. Aluminum everything. Skids expecially can add a ton of weight and steel isn't needed for what you're doing. I have a lear fiberglass topper on my truck. Very solid unit but heavy! Mine is around 300 pounds. It came on the truck but at some point I'll probably trade it out for aluminum. All that heavy stuff adds up FAST. Time to start a build thread.

mvbeggs
01-15-2012, 06:02 PM
Hey congratulations! stick or auto? My advice would be to keep it light. Aluminum everything. Skids expecially can add a ton of weight and steel isn't needed for what you're doing. I have a lear fiberglass topper on my truck. Very solid unit but heavy! Mine is around 300 pounds. It came on the truck but at some point I'll probably trade it out for aluminum. All that heavy stuff adds up FAST. Time to start a build thread.

It's an auto. Manuals are slim to non-existent around here.

Know what you mean about the skids. The LoD slider's on the Jeep are heavy, but durable. I'm anticipating the biggest decisions on this build is going to be the weight vs strength issue. I'll be tracking the weight coming off vs what is going back on as well as the influence of the weight change on gas mileage.

I'm looking forward to the build.

Thanks again for the help.

Rocket-scientist
01-15-2012, 11:19 PM
The goal is to build a rig that will get 15-16mpg and able to tackle moderate trails.



This weekend I went to Mohave area with some friends. I only got 15.5 on the way out there, mostly uphill from San Clemente. After a day of wheeling on old mining roads, running the truck this morning for some heat, and 60 highway miles I was still in the mid 15's at the next fill up. After that, all highway on the 15 back home I'm just under 17. YMMV, but that's what this thread is about, right?

mvbeggs
01-15-2012, 11:42 PM
This weekend I went to Mohave area with some friends. I only got 15.5 on the way out there, mostly uphill from San Clemente. After a day of wheeling on old mining roads, running the truck this morning for some heat, and 60 highway miles I was still in the mid 15's at the next fill up. After that, all highway on the 15 back home I'm just under 17. YMMV, but that's what this thread is about, right?

YMMV, but that's what this thread is about, right?


LOL, not exactly...:D I may have wandered just a bit from the original topic. Sorry about the hijack.

Glad to hear that you're running in the mid 15's. That's where I hope to end up. How are you equipped? (i.e. armor, engine, auto or manual, wheels, tires, suspension)

Should we start another thread?

steve103
01-16-2012, 04:47 PM
back to topic. what is the gearing in a 05-10 tacoma trd? is it 410 or 488,then i could swap out and maybe get rear locker with it.

Rocket-scientist
01-17-2012, 04:48 PM
back to topic. what is the gearing in a 05-10 tacoma trd? is it 410 or 488,then i could swap out and maybe get rear locker with it.

3.73 :(

Rocket-scientist
01-17-2012, 04:51 PM
LOL, not exactly...:D I may have wandered just a bit from the original topic. Sorry about the hijack.

Glad to hear that you're running in the mid 15's. That's where I hope to end up. How are you equipped? (i.e. armor, engine, auto or manual, wheels, tires, suspension)

Should we start another thread?

ARB bumper, winch with synthetic line, All Pro rockers, 4 piece bud built skids, ARB fridge, Tool box with tools, small compressor and recovery gear, 5 gallons each gas and water.