Still dont have a lot of miles, but even my wife commented how powerful the engine felt in my '19 with plenty of excess weight and the Nitro 4.3's. Might be 4.88's for the '15s-older and 4.3s or 4.88s depending on tire size and use for '16 and up...
4.30 or 4.88 re-gear
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I have Nitro 4.88's from Just Differentials in my 100 and the amount of metal (after the break in) has been disappointing. Gears were installed and setup by ACC so no shadetree mechanic job either. I've had Marshall at Trollholes taking care of my 100 and he and I both have been a little disheartened with what we see on fluid changes.
Don't want to scare anyone away from it as I'm in the minority I'm sure but be assured there are those of us that have written that check and it's not always roses! At this point it will cost me another large sum of money to go in and sort it out so I plan on running them for awhile and then will end up buying another set of gears if wear continues or worsens.
bloc
SILVER Star
Sorry to hear that. You definitely weren’t the first person I’ve seen write about this, and with my tendency to pile miles onto my trucks wear resistance plays a large part in my decisions on things like this.
It's been years since the install but 500mi IIRC? Only 25,000 since install. Fluid changed at 10k looked like hell, changed it again at 20k and it was still unimpressive. Have a pic Marshall sent me somewhere I'll try to post if anyone is interested.
I have nitros as well and will be changing fluid every 15k or so. There was some metal In the breakin oil and the gears were louder for about 1500 miles. Not noticing them now noise wise. Still love the added functionality and would do it again.
There aren't many options in this space anyhow.
There aren't many options in this space anyhow.
Reviving an old thread. I've got the skinny kenda 35s installed. I'm torn between 4.30 and 4.88. Here's why: on my GX470 5 speed (a750 trans) I had the same tires and went for 4.56 gearing because that's what was recommended over 4.10 on 35s. The GX had a set if drawers full time I'm the rear, rear dual swingout, rack, lifted, front hidden winch with 10k winch. That truck was way low on power vs the 3ur. My goal on the LX is to have dual swingout rear, rack, front hidden winch (no exposed tire air brake system from a full bumper 
) and don't plan on an aux tank either or RTT, although I will strap stuff to the rack for trips. I 'unload' my rigs after trips. Im not one to constantly have all my gear strapped to the truck 24/7 (awinings, tents, recovery boards, etc). My problem on the GX is that with the 4.55 gears the engine was screaming along at 2200-2300 rpm at 75. Some of you may not consider that a lot of rpm, but I did, especially on long hwy trips. Sure, it didn't downshift up a grade and generally just pulled it's way through most grades fine, even when loaded up and towed my smallish 4500 lbs boat/trailer just fine. Having CC engaged and it not suddenly downshift and scream its way back to the commanded speed, while someone was passing me in the other lane, making me look like an ass that wanted to race, was also nice lol
Now, to the LX. Can I get that same result with 4.30s? My 'want' or goal is to be below 2k rpm at 70, but also hopefully not have it downshift as often as it has to do now on the 3.90s with 35s. Here's the other factor, I plan to supercharge the LX (it's a 14). Im banking on the added tq from the blower making up for any drawback to going with 4.30s as far as it not having to downshift up an overpass or small grade. I figure the blower will make up the difference I would get from the 4.88s in those scenarios. Is my reasoning off on that? My GX was supercharged and I noticed that on the same small bridge with the 4.56 gears, it held speed (because it was making about 1psi of boost at that point) without downshifting. On that same bridge, with the 4.56 gears, same speed (40 mph), without the SC, it would loose enough steam to require the need for a downshift to maintain itself.
Basically, 4.30s/35s on the LX, with an SC, can I have my cake and eat it too? Or, get close to it? The SC is happening no matter the gearing choice I make based on your recommendation. I'm just that kind of guy that likes forced induction and power whether it be a lawnmower (is been done lol) a waverunner, or car/truck.l etc.
Thanks for any insight you all can provide and for taking the time to read and reply.
) and don't plan on an aux tank either or RTT, although I will strap stuff to the rack for trips. I 'unload' my rigs after trips. Im not one to constantly have all my gear strapped to the truck 24/7 (awinings, tents, recovery boards, etc). My problem on the GX is that with the 4.55 gears the engine was screaming along at 2200-2300 rpm at 75. Some of you may not consider that a lot of rpm, but I did, especially on long hwy trips. Sure, it didn't downshift up a grade and generally just pulled it's way through most grades fine, even when loaded up and towed my smallish 4500 lbs boat/trailer just fine. Having CC engaged and it not suddenly downshift and scream its way back to the commanded speed, while someone was passing me in the other lane, making me look like an ass that wanted to race, was also nice lolNow, to the LX. Can I get that same result with 4.30s? My 'want' or goal is to be below 2k rpm at 70, but also hopefully not have it downshift as often as it has to do now on the 3.90s with 35s. Here's the other factor, I plan to supercharge the LX (it's a 14). Im banking on the added tq from the blower making up for any drawback to going with 4.30s as far as it not having to downshift up an overpass or small grade. I figure the blower will make up the difference I would get from the 4.88s in those scenarios. Is my reasoning off on that? My GX was supercharged and I noticed that on the same small bridge with the 4.56 gears, it held speed (because it was making about 1psi of boost at that point) without downshifting. On that same bridge, with the 4.56 gears, same speed (40 mph), without the SC, it would loose enough steam to require the need for a downshift to maintain itself.
Basically, 4.30s/35s on the LX, with an SC, can I have my cake and eat it too? Or, get close to it? The SC is happening no matter the gearing choice I make based on your recommendation. I'm just that kind of guy that likes forced induction and power whether it be a lawnmower (is been done lol) a waverunner, or car/truck.l etc.
Thanks for any insight you all can provide and for taking the time to read and reply.
Reviving an old thread. I've got the skinny kenda 35s installed. I'm torn between 4.30 and 4.88. Here's why: on my GX470 5 speed (a750 trans) I had the same tires and went for 4.56 gearing because that's what was recommended over 4.10 on 35s. The GX had a set if drawers full time I'm the rear, rear dual swingout, rack, lifted, front hidden winch with 10k winch. That truck was way low on power vs the 3ur. My goal on the LX is to have dual swingout rear, rack, front hidden winch (no exposed tire air brake system from a full bumper
Now, to the LX. Can I get that same result with 4.30s? My 'want' or goal is to be below 2k rpm at 70, but also hopefully not have it downshift as often as it has to do now on the 3.90s with 35s. Here's the other factor, I plan to supercharge the LX (it's a 14). Im banking on the added tq from the blower making up for any drawback to going with 4.30s as far as it not having to downshift up an overpass or small grade. I figure the blower will make up the difference I would get from the 4.88s in those scenarios. Is my reasoning off on that? My GX was supercharged and I noticed that on the same small bridge with the 4.56 gears, it held speed (because it was making about 1psi of boost at that point) without downshifting. On that same bridge, with the 4.56 gears, same speed (40 mph), without the SC, it would loose enough steam to require the need for a downshift to maintain itself.
Basically, 4.30s/35s on the LX, with an SC, can I have my cake and eat it too? Or, get close to it? The SC is happening no matter the gearing choice I make based on your recommendation. I'm just that kind of guy that likes forced induction and power whether it be a lawnmower (is been done lol) a waverunner, or car/truck.l etc.
Thanks for any insight you all can provide and for taking the time to read and reply.
Part of the difference to your previous experience is that the 5.7L is a brute and makes more torque and power off idle than every other Toyota model/drivetrain. An SC is only going to add to that. The 5.7L doesn't need the type of gearing that lower end models do, including the GX, to be setup for significant overland weight.
I've already shared - I do a lot of towing and overland trips. 15,620lbs combined weight when towing with 35s. 4.3 is perfect. 4.88 would be excess RPM, on the freeway in 6th gear when unladen.
To put things in perspective as these are not minor adjustments we're talking about
- 4.3 is a 10% correction to stock 3.9s
- 4.88 is a 25% correction to stock 3.9s
- 4.88 is 15% more gearing than 4.3! Let that sink in, 15% more is almost like a whole ratio in the 6-speed transmission. It would be like permanently rolling in 5th without the ability to grab 6th on the highway.
4.3s will give you your cake. It's not just gearing, as shift logic and torque lockup will behave like stock and not feel like a 10 yr old tuned the transmission.
Thanks! I really appreciate the response. Your experience and posts in other threads is what had me sold on 4.3s but it seemed everyone was doing 4.88s and saying it was the best option. 4.3s it is then!
4.88s don't suck, but 4.3s should meet most use cases, maybe even better. Depends what you're after.
I thought the original ratio was a bit passive, and didn't want to leave it long after changing ratios, so put in 4.88s. Lots more have converted now and report its just fine on 4.3s. I don't regret 4.88s. I like short gearing. I don't have any issue with the RPM I run on the freeway, it's a non-issue. And I like the much better engine braking and general around town drivability of the higher ratio.
As for the shifting, I get a lot more of it now that I changed, plugs, coils, and A/F and O2 sensors. That's made for an engine that is more sensitive to the loads it is under, and it shifts down more. I also get better HWY MPG, particularly on premiuim, than I have been over the last five years.
I thought the original ratio was a bit passive, and didn't want to leave it long after changing ratios, so put in 4.88s. Lots more have converted now and report its just fine on 4.3s. I don't regret 4.88s. I like short gearing. I don't have any issue with the RPM I run on the freeway, it's a non-issue. And I like the much better engine braking and general around town drivability of the higher ratio.
As for the shifting, I get a lot more of it now that I changed, plugs, coils, and A/F and O2 sensors. That's made for an engine that is more sensitive to the loads it is under, and it shifts down more. I also get better HWY MPG, particularly on premiuim, than I have been over the last five years.
Another great point of view. Thanks! My 14 has 116k on it. I've had it for 1 month but already knew what I wanted to do with it based on my experience with my GX. So it got wheels and tires and I serviced the AHC with new globes and fluid already. So, maintenance, proactive maintenance especially, is top on my list. I'll be checking plugs, coils, etc soon.
To be fair to @grinchy 's point. If you know what you want for shorter gearing, potential to go beyond 35s, have substantial aero/drag loads like front bumper, roof rack, MT tires, don't mind the increased cruise RPM with incremental efficiency trades, lower crawl ratio, go for the 4.88s.
Too bad 4.56s aren't an option.
Too bad 4.56s aren't an option.
Yeah. I can see both sides of the argument for 4.88s. I just don't think I'll be that heavy. The worst aero impact will be from roof rack but that will be a prinsu with a wind faring and from my experience with my prinsu on my GX before gears/after gears was little to no difference in vehicle performance, and that was with a much lower power 2uz. Also, that truck had 35s and a 3 inch static lift. I LOVE AHC and the fact it lowers at highway speeds. All that is to say, everything pints to "do 4.30s".
The tradeoff is also not worth it since the 4.88s would really only be THAT beneficial to me on trips, which happen maybe three or four times a year. As for offroad, I dont crawl. The most I've ever done were passes in Colorado and white rim trail in Utah which has Murphys hogback, Lathrop canyon and a few other spots that are barely technical. No real rock crawling in the 5 years I owned the GX as modified as it was. So the ratios of 4hi in 2nd/3rd for low speed stuff and 4lo for really low speed stuff are sufficient.
Thanks again for all the input!
With 34s I wish I’d gone 4.30 gears. Now that I have 35s I really like 4.88s. The shifting is much more refined than 34s on 4.88 gears. So I do think gear choice depends on tire size a lot.
OEM my 2016 had 31.6 tires and 3.88 gears
With 4.88 gears and 34" tires that ration is approx 17% lower gearing.
34 / 31.6 x 3.88 / 4.88 = 17% difference.
My mileage dropped approx. 17% mpg.
Have not been towing with the new gears yet .. so I have no opinion there.
No locker is available for the front 3.88 gears.
One thing to note is: my Nitto RT 34" tires on the LC200 are TALLER than my Toyo 35 x 12.5 x 17 tires on my Jeep.
With 4.88 gears and 34" tires that ration is approx 17% lower gearing.
34 / 31.6 x 3.88 / 4.88 = 17% difference.
My mileage dropped approx. 17% mpg.
Have not been towing with the new gears yet .. so I have no opinion there.
No locker is available for the front 3.88 gears.
One thing to note is: my Nitto RT 34" tires on the LC200 are TALLER than my Toyo 35 x 12.5 x 17 tires on my Jeep.
Unless I'm mistaken, your 2016 had 3.307 gears factory so you're looking at a 27% difference.
Definitive 200-series Gearing Reference
EDIT: Expanding tables for 8-speed and 40s So I had a little time this morning to put together a chart combining transmission gearing of 6-speed vs 8-speed, diff ratios, and tire sizing into an overall gearing reference. Hoping this will be useful for those trying to understand how their...
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Yes. But only when towing. If I can run in 5th gear now on 4.88s instead of 4th on 3.90s I gain about 0.5mpg. So I get a bit over 8mpg instead of upper 7s. Still awful. And if I can’t keep the torque converter locked in 5th and have to drop to 4th I’m down in the low-mid 6s. Note this is on 34s.
Otherwise no, highway mileage is worse. Not appreciably, but maybe 10% less. City mileage is better by 10-20% if I drive like a grandpa. But I don’t so in most cases my city mileage looks similar.
Not entirely sure what mpg looks like on the new 35s.
My highway MPG improved noticeably going from 285/70r17s to 35x10.50r17s without regearing. Perhaps because of the lower RPM while cruising. I'll see how that changes once I put my bumpers back on. I'm still on the fence about regearing.
Same tire model? I think tire compounds and tread patterns have a lot to do with mileage, so if they are different tire models or brands that would easily explain the mpg difference
