5th Gen Gear Swaps??

[jpclark]

Hey all -

'Lone Runner' currently runs full Shrockworks armor (front bumper, skids, sliders) as well as Gobi rack, light bars, etc. She's also had a body mount chop so she can run 285 BFG KM2s. As if I've taken enough of an MPG hit (down to 13/14 mpg) she's currently at Shrockworks serving as their prototype for their revised rear bumper. With all this, I've decided she MUST go for a gear swap. I was originally thinking 4.10, but heard a valid argument for going as far as 4.56, given that I'm mostly driving in town, but also tow a boat on highway and wheel heavily. I'm curious.. has anyone any experience swapping gears in a 5th gen yet? I'd love to hear your experiences/recommendations.

 

[FactoryRide]

Several people have taken the plunge to regear theirs. I think you're gonna have an issue getting 4.10s seeing as our trucks have only two options that I know of.

Everyone I know of has done the 4.56. Nitro has released 4.88s sometime here recently though. I saw those on East Coast Gear Supply's website. 4.56 seems to be the ticket. 4.88s I believe would be a little too much unless you plan to run 35s or bigger.
[MENTION=8206]harper7[/MENTION] [MENTION=89562]bimrunner[/MENTION] [MENTION=78273]Jeremy556[/MENTION]

 

[jpclark]

Several people have taken the plunge to regear theirs... Everyone I know of has done the 4.56. [MENTION=8206]harper7[/MENTION] [MENTION=89562]bimrunner[/MENTION] [MENTION=78273]Jeremy556[/MENTION]

Thank you sir! That's good news as I do believe I'm leaning that way from what I'm hearing. What have folks seen about mileage? Has performance met or exceeded factory with all the extra weight? As I mentioned, right now I'm down to about 13/14. Heck... on highway she can not even stay in overdrive right now.

 

[harper7]

Hey all -

'Lone Runner' currently runs full Shrockworks armor (front bumper, skids, sliders) as well as Gobi rack, light bars, etc. She's also had a body mount chop so she can run 285 BFG KM2s. As if I've taken enough of an MPG hit (down to 13/14 mpg) she's currently at Shrockworks serving as their prototype for their revised rear bumper. With all this, I've decided she MUST go for a gear swap. I was originally thinking 4.10, but heard a valid argument for going as far as 4.56, given that I'm mostly driving in town, but also tow a boat on highway and wheel heavily. I'm curious.. has anyone any experience swapping gears in a 5th gen yet? I'd love to hear your experiences/recommendations.

Nobody makes a 4:10 that works in our 8.2 rear diffs. Only 4:56's and just lately 4:88's. Many of us on here and the FJ forum running 4:56's for years with the new rear ends without a hitch.
ASSEMBLED 3rds & Clamshells - 2010+ 4 Runner is your best bet in my opinion and just swap them out with their exchange program and have experience on these. I had them build my 3rd member and clamshell with ARB lockers about 60k miles and almost 4 years ago and still running smooth with no problems.

 

[bimrunner]

Hey all -

'Lone Runner' currently runs full Shrockworks armor (front bumper, skids, sliders) as well as Gobi rack, light bars, etc. She's also had a body mount chop so she can run 285 BFG KM2s. As if I've taken enough of an MPG hit (down to 13/14 mpg) she's currently at Shrockworks serving as their prototype for their revised rear bumper. With all this, I've decided she MUST go for a gear swap. I was originally thinking 4.10, but heard a valid argument for going as far as 4.56, given that I'm mostly driving in town, but also tow a boat on highway and wheel heavily. I'm curious.. has anyone any experience swapping gears in a 5th gen yet? I'd love to hear your experiences/recommendations.

4.56 is perfect with armor and 34/35 inch tires. Honestly, I'd be worried the 4.88 was getting a little thin in the 8.2 housing and probably a bit low for our rigs. 4.56 is your ticket. Been very happy with mine.

 

[Jeremy556]

Yep - only available aftermarket gears are 4.56 and 4.88 from Nitro. The 4.56s work great with 285/70/17 tires. I got complete clamshell and 3rd from East Coast Gear Supply, and highly recommend them. Perfect time to add ARB locker(s).

You could potentially get Toyota 3.9 gears meant for a 2010+ 6 speed FJC, but they'll probably be more than twice the price of Nitro.

 

[bimrunner]

Thank you sir! That's good news as I do believe I'm leaning that way from what I'm hearing. What have folks seen about mileage? Has performance met or exceeded factory with all the extra weight? As I mentioned, right now I'm down to about 13/14. Heck... on highway she can not even stay in overdrive right now.

You prob will gain a small tad back (read 1mgp) if you have 34s or 35s. If not, you will just be happier driing with the 4.56 gears. No more gear hunting and such. Smooth again is a good thing!

Edit: get the air lockers. Now is the time. You don't want to crack the clams again! do it once and do it right!

 

[Jeremy556]

Thank you sir! That's good news as I do believe I'm leaning that way from what I'm hearing. What have folks seen about mileage? Has performance met or exceeded factory with all the extra weight? As I mentioned, right now I'm down to about 13/14. Heck... on highway she can not even stay in overdrive right now.

Mileage is about what it was before for me, around 14. It feels faster than stock, even with mud tires, full armor, bumper, winch, etc. This is with 33" tires.

 

[Jetboy]

4.56 is perfect with armor and 34/35 inch tires. Honestly, I'd be worried the 4.88 was getting a little thin in the 8.2 housing and probably a bit low for our rigs. 4.56 is your ticket. Been very happy with mine.

4.88 should be no problem. The lower ratio the thicker the ring gear . The pinion gets fewer teeth. 4.88 pinions are thick enough for pretty hard use in other 8" diffs. Its really when u jump from 5.29 to 5.71 that the pinion gets really weak.

 

[Zeusmotorworks]

Talk to Chase at ECGS as others have said. Great guy to deal with and their core policy is the best in the business. 4.56 gears is what you want. On this rearend the pinion IS getting thin with the 4.88s. Also, I did these in my FJ with the ARB in front. Works so well I wish I didn't have the Toyota e-locker in the back so I could have an ARB there as well. Sooooooo much better than the e-locker

 

[wfo9]

Funny, I just saw your post on the CTOR facebook page and I responded. I'm in Austin. I happen to have 4.56 gears in my truck with 285 33s.... I plan to eventually run 34s, but there is only about a 100 rpm difference from 33->34s (in 5th gear).

Overall it is great, but mpg has dropped a bit more on my truck. I was avg about 16-17 before the gears and now I'm about 14-15 (might be able to squeeze 17 if I'm super conservative and run < 65pmh). I don't have bumpers yet, (but I have all the other armor... I think the gears also make me a little more aggressive on the go pedal, since it is quite a bit quicker overall.

The only downside (and it is somewhat significant) is that the truck seems to want to cruise about 65-70mph on the hwy. It will still run just fine at 80mph, but it feels like it just wants to go slower with the rpms up that high. The mpg goes to total crap over 70mph. Your mind keeps thinking there will be one more gear, but it ain't there. The good thing is it never needs to downshift on hills unless they are crazy grades. Should be much better for towing.

The improved crawl speed off-road is great and I also went with ARB lockers front and rear when I did it. The lockers really take things to a new level. As you know, ATRAC will get you though most every situation, but the lockers will let you do it with more grace and less thrashing. And there are some things you can do that ATRAC just can't deal with (like deep mud...)

 

[Jeremy556]

Overall it is great, but mpg has dropped a bit more on my truck. I was avg about 16-17 before the gears and now I'm about 14-15 (might be able to squeeze 17 if I'm super conservative and run < 65pmh)

I think I was around 16mpg overall with 285 Duratracs and stock front bumper, but going to MTRs and Shrock bumper dropped 2-3mpg. Cruising at 60 on flat roads I can still pull 18mpg, but the drag really kills it above that speed, and all of the highways are 75+ around here.

 

[Zeusmotorworks]

On the FJ I actually went up a couple MPG because I'm not flooring it out of frustration anymore. However, my driving is mixed city/hwy. If it were all HWY at 75 or more MPH, I could see it being worse. If the Wife ever decides to outfit her 2014 TEP like the FJ (freakin heavy), it too will get the 4.56 treatment.

 

[marshal]

if i have this truck long enough with IFS, i fully intend to go with 4.88s. if i have my way and sling a solid axle under the front 5.38s are going in. don't fear the gear.

 

[Jetboy]

Talk to Chase at ECGS as others have said. Great guy to deal with and their core policy is the best in the business. 4.56 gears is what you want. On this rearend the pinion IS getting thin with the 4.88s. Also, I did these in my FJ with the ARB in front. Works so well I wish I didn't have the Toyota e-locker in the back so I could have an ARB there as well. Sooooooo much better than the e-locker

I'm confused about this. Why do you say the pinion is getting thin? It should be very marginally weaker than the pinion of a 4.56 - only because there is one less pinion tooth and marginally less contact surface. It's not until you get lower than 5.29 that the shaft diameter is smaller at the gears. Are there people blowing up 4.88 gears? I ask because it seems like in my experience 5.29s in 8" axles are pretty much ubiquitous in rock crawling and seem more than adequate for anything up to 37's.

I abuse the shit out of my 5.29s in my trail rig on 39's with lockers at both ends and never think twice about it. The axles and hubs are the weak links. Granted they are both 9.5" land Cruiser diffs - the two aren't all that far off. Would be nice to get the 9.5 in the 4runner. Considering it's just as big and heavy as a 80 series, maybe it should have the larger rear axle.

FWIW - 4:10's would be nearly perfect gearing for 33's if we could get them. I wouldn't want 4.88's for the gearing unless i were going up to maybe 35's but probably 37's or larger. And at that point with the weight of the 4runners, I'd probably go solid axle swap, build a front axle out of the rear and put the rear 8.2 diff in a front axle and find 9.5" centered housing for the rear from a 4.7L tundra.

 

[wfo9]

I'm confused about this. Why do you say the pinion is getting thin? It should be very marginally weaker than the pinion of a 4.56 - only because there is one less pinion tooth and marginally less contact surface. It's not until you get lower than 5.29 that the shaft diameter is smaller at the gears. Are there people blowing up 4.88 gears? I ask because it seems like in my experience 5.29s in 8" axles are pretty much ubiquitous in rock crawling and seem more than adequate for anything up to 37's.

I abuse the shit out of my 5.29s in my trail rig on 39's with lockers at both ends and never think twice about it. The axles and hubs are the weak links. Granted they are both 9.5" land Cruiser diffs - the two aren't all that far off. Would be nice to get the 9.5 in the 4runner. Considering it's just as big and heavy as a 80 series, maybe it should have the larger rear axle.

FWIW - 4:10's would be nearly perfect gearing for 33's if we could get them. I wouldn't want 4.88's for the gearing unless i were going up to maybe 35's but probably 37's or larger. And at that point with the weight of the 4runners, I'd probably go solid axle swap, build a front axle out of the rear and put the rear 8.2 diff in a front axle and find 9.5" centered housing for the rear from a 4.7L tundra.

Just to add, My understanding is the 8.2 is really just a redesigned 8.0 built with stronger parts, it still measures 8.0. They have a so called 8.4 open diff for the Tacoma, but it measures 8.2 (not sure which is stronger).

So far, it seems the 8.2s have been holding up really well. The front clamshell is the weak point for sure.

I think a 5th gen IFS would stay together on 35s just like the FJs. I really want 35s :hungry:

 

[Zeusmotorworks]

I'm confused about this. Why do you say the pinion is getting thin? It should be very marginally weaker than the pinion of a 4.56 - only because there is one less pinion tooth and marginally less contact surface. It's not until you get lower than 5.29 that the shaft diameter is smaller at the gears. Are there people blowing up 4.88 gears? I ask because it seems like in my experience 5.29s in 8" axles are pretty much ubiquitous in rock crawling and seem more than adequate for anything up to 37's.

I abuse the shit out of my 5.29s in my trail rig on 39's with lockers at both ends and never think twice about it. The axles and hubs are the weak links. Granted they are both 9.5" land Cruiser diffs - the two aren't all that far off. Would be nice to get the 9.5 in the 4runner. Considering it's just as big and heavy as a 80 series, maybe it should have the larger rear axle.

FWIW - 4:10's would be nearly perfect gearing for 33's if we could get them. I wouldn't want 4.88's for the gearing unless i were going up to maybe 35's but probably 37's or larger. And at that point with the weight of the 4runners, I'd probably go solid axle swap, build a front axle out of the rear and put the rear 8.2 diff in a front axle and find 9.5" centered housing for the rear from a 4.7L tundra.

Slow down, you are throwing multiple applications into the mix and gears are not just "gears". When I say "getting a little thin", I'm not talking about the shaft it's self, but the central mass of the pinion head. Of the two, we've had more 4.88 rear ends get busted than 4.56 on 35s. Granted, that's the FJ side of the house and a relatively small sample group (same rear end depending on years), but the people I wheeled with at the time primarily wheeled rock/limestone shelf.

If the guy is just playing in the mud, I'm sure he would be fine for the most part with the 4.88s. Then again, I doubt he'd want to take the hit at the pump from his comments, therefore we are back to 4.56s. Having as much grey in my hair and coming from aerospace manufacturing, even when I speculate, there has to be some corroborating evidence that lends to a conclusion from past experience. So with that, I bow out. If you have application specific evidence to the contrary please educate us all. I am however, done as I have very specific feelings about arguing on the interweb and I in no way want to belittle/downplay/nor discredit anyone else. Just like everyone else, I have an opinion... and you know what they say about those.

 

[cbielat]

I have 4.56 waiting to be installed with an ARB air locker for the rear, currently. Still need to buy the master rebuild kits. From talking with others and [MENTION=89562]bimrunner[/MENTION], the 4.56 seem to be the way to go. I'll be throwing 34's on as well. Since the front is going to be opened up, I think I'm going to get another ARB locker for it as well.

 

[Zeusmotorworks]

I have 4.56 waiting to be installed with an ARB air locker for the rear, currently. Still need to buy the master rebuild kits. From talking with others and [MENTION=89562]bimrunner[/MENTION], the 4.56 seem to be the way to go. I'll be throwing 34's on as well. Since the front is going to be opened up, I think I'm going to get another ARB locker for it as well.

Take it from someone who has the ARB front/e-locker rear... instant satisfaction. ARB instantly locks/unlocks. The OE e-locker requires a little rolling distance more times than not to engage/disengage. Also remember that you have to be mindful of the steering angle in front when locked up and gassing it. Bad things can happen.

 

[cbielat]

Take it from someone who has the ARB front/e-locker rear... instant satisfaction. ARB instantly locks/unlocks. The OE e-locker requires a little rolling distance more times than not to engage/disengage. Also remember that you have to be mindful of the steering angle in front when locked up and gassing it. Bad things can happen.

Yeah man, I don't have the elocker hence why I'm going the ARB air locker route. I just messaged [MENTION=106176]wfo9[/MENTION] asking his experiences with his front. From what I've read researching is exactly what you have mentioned regarding how/when to use it. Just need to be careful it sounds.

Also, are you running the ARB compressor? I have the CKMA12. If you have that one, how did you mount it? I need to get a mounting plate from somewhere.