SQRRRL
SILVER Star
when loaded with the family/roof box and or off road trailer on 33’s 4.88 would be the ticket. I’m looking forward to the mod.
To re-gear or not to re-gear? (1 Viewer)
- Thread starter BetoLC
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I toy with the idea or re-gearing as I tow to almost the full gross combined weight rating (GCWR) of 14,645 lbs. Here's a gearing reference put together awhile ago.
forum.ih8mud.com
Excerpt:
Gearing is one of those things that's a balance. What I would really love is the newer 8-speed with it's gigantic 1st to 8th gear spread that's some 25% better. With bottom, top, and everything in between.
I run 33s with no other significant gearing loads when unladen. A 4.3 would put me to just better than stock which would be perfect for my laden and unladen use. 4.88s would be interesting, but perhaps would be too short at higher speeds (with stock body aero) where I feel like I want to reach for another gear.
The 5.7L has a great, flat, and flexible powerband that I rarely miss even stock gearing at full load. Only situation where I find myself wanting more gear is 7%+ grades at high elevations, particularly when starting from a stop. At speed, she does fine. Fixing the gearing back to stock would be ideal for my setup, but I don't feel like it's absolutely necessary with the tractable motor.
One thing that may help some deal with hunting for gears is to use sport mode. Having driven over 10k miles towing, I always use sport mode to limit top gear to 4th (S4). It's no harder to set to S4 as it is to "D", and the transmission does the rest, using every gear up to the particular gear.
S5 on 6-speeds for built rigs could probably work sufficiently well. If I had the 8-speed, I would use sport mode to also limit top gear as necessary for the rig setup. It already has enough gearing in 1st for days (almost as good as a 6-speed with 4.88 on 31s).
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...
forum.ih8mud.com
Excerpt:
Gearing is one of those things that's a balance. What I would really love is the newer 8-speed with it's gigantic 1st to 8th gear spread that's some 25% better. With bottom, top, and everything in between.
I run 33s with no other significant gearing loads when unladen. A 4.3 would put me to just better than stock which would be perfect for my laden and unladen use. 4.88s would be interesting, but perhaps would be too short at higher speeds (with stock body aero) where I feel like I want to reach for another gear.
The 5.7L has a great, flat, and flexible powerband that I rarely miss even stock gearing at full load. Only situation where I find myself wanting more gear is 7%+ grades at high elevations, particularly when starting from a stop. At speed, she does fine. Fixing the gearing back to stock would be ideal for my setup, but I don't feel like it's absolutely necessary with the tractable motor.
One thing that may help some deal with hunting for gears is to use sport mode. Having driven over 10k miles towing, I always use sport mode to limit top gear to 4th (S4). It's no harder to set to S4 as it is to "D", and the transmission does the rest, using every gear up to the particular gear.
S5 on 6-speeds for built rigs could probably work sufficiently well. If I had the 8-speed, I would use sport mode to also limit top gear as necessary for the rig setup. It already has enough gearing in 1st for days (almost as good as a 6-speed with 4.88 on 31s).
Taco2Cruiser
Crazy American Off Road
So when I got my ‘11 and just finished putting an average lift on it, bull bar, and 33 muds I headed to California from Texas and was like “NOOOPPPE. This truck is getting 4.88s the second I get to Georgia!” Now that I tow a lot, I wish I had 5.29s.
I don’t talk about towing much on here for a few reasons, but when I looked back at the last two years. I’m either towing the Kimberly (4,000 lbs or something like that, depends on if the water tanks are full), towing the buggy (6,700 pounds), or towing the truggy with the show booth setup (8,400 pounds, GVWR is 15,300 give or take a few hundred pounds if one or two of the guys ride along with me)
I almost never drive my 200 without something behind it, and going up mountains or heading into head winds, gives a little more be desired in my opinion. I’ll fall into 3rd sometimes which I absolutely hate as lock up is only for direct and overdrive. So the tranny is just burning itself up at those gears, and I do everything I can to stay away from that.
I cryogenically froze my trans and diffs, put a fuel cooler on the return line, and polished the entire valve train when I took my 5.7 apart, which helps a fair amount, but yea, in my opinion, the 5.7 needs to be above 2,600 rpms to have the grunt to pull heavy loads. Especially heavy loads that are not an aerodynamic travel trailer, but these tubed out buggies with either 40s or 52s tires that are like parachutes back there.
So for me, being geared to never have to drop below direct is the only way I want my truck to be, and I can't get that.
I guess the point of this dumb little story of mine is that for the masses, I think that on a 6 speed, 4.88s is the only way. It doesn’t loose MPG, it feels great when driving around, and it still will hit 110 mph (yes... I know... I shouldn’t have) and the motor isn’t screaming at all.
I personally prefer a tad bit of higher RPMs if it means I can get a slight reduction in engine load. The 5.7 is an amazing motor, but there a few things deep in there that I don’t think like having a lot of pressure applied to them, like something as simple as the spark plug tube gasket. Then there is the trans wanting to shift all the time.
Oh speaking of shifting, so my parents tow the Kimberly also with their bone stock ‘18, and I gotta say, I see why the Australians are still getting the 6 speed. Very gutless unless you jam on it in my opinion as having more closer gears doesn’t help. The 5.7 needs to rev, so let it. It’s a gas motor, not a diesel, it wants to rev. Basically all I notice is with the 8 speed, you spend so much time jumping around, that you just burn more fuel and add more T/C heat.
If I had their 8 speed and only the Kimberly, with its stock front bumper and 32s, I’d do 4.30s also to get a tag bit more RPMs and make it to where I don’t feel like I have to lay into the accelerator on every little hill. If it had a bull bar, 4.88s in a heartbeat.
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While we're taking positions on what each of us would prefer, it's obvious that it's setup dependent, with a big dose of preference, and primary usage. My rig is largely stock in terms of weight and aero loads when unladen, hence my preference. I've also played with ratios and re-geared third members and swapped multiple trannies in my previous vehicles so I have a feel for where I want my gearing.
I agree for a more built-up rig with more base weight, larger tires, armor and racks, etc., that 4.88s could be the right choice. More extreme still - sure more gearing.
It's never without trade though. There's is a sweet spot for mpg when gearing. A heavily laden rig may benefit from more technically optimal gearing and eek out more MPG as it lets the engine operate at lower load points that can be more efficient. Past that optimal point, efficiency will go down due to reciprocating and windage losses as a result of excess gearing.
I agree for a more built-up rig with more base weight, larger tires, armor and racks, etc., that 4.88s could be the right choice. More extreme still - sure more gearing.
It's never without trade though. There's is a sweet spot for mpg when gearing. A heavily laden rig may benefit from more technically optimal gearing and eek out more MPG as it lets the engine operate at lower load points that can be more efficient. Past that optimal point, efficiency will go down due to reciprocating and windage losses as a result of excess gearing.
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How do you know when to re-gear? My truck is slow AF during acceleration lol and not sure where to start looking at gears. Any help would be greatly appreciated!
I have the 8 speed trans.
Here is why I’ve been considering it, just don’t take this as some expert answer to your question.
I went up in tire size to 285/70. This isn’t drastic but I also tow a 4000 trailer and have bumpers and skids and tons of other weight like kids and stuff.
We’ve been on the road for the last 10 days or so and the long hauls up and over elevation in New Mexico, Colorado, and Utah have been tough. I’m either 4500 rpm’s in 2nd hoping to maintain 45 then as I approach 5000rpms shift into 3rd… rpm’s now 3200 and falling. Speed falls from 50ish down to 38 or so and then I’m back into 2nd to wind out the tach and do it all over. Another scenario I found was we did the first half of Rimrocker trail, right out the gate it’s long slow climbs, nothing crazy but I’m searching for gear and there’s just a dead spot between 2 and 3 and 3 and 4. I just can’t move the needle at 3000 rpm’s. Trans and torque converter temps get high, like 250°. It doesn’t help that I have all the fun heavy mods.
When not towing it’s manageable, when I am towing I’m watching the tach and temp gauges on the OBDLink app thingy like a hawk.
Tell us your model year and mods. Particularly those that add a lot of weight and aero impacts. And if you do any serious towing.
I did 4.88s on the 6speed as part of the prep for 35” tires.
I already had a steel rear with swing, and planned on adding the usual things over time. I didn’t want to lose drive ability as inevitably there is a lot of freeway before the trails. So it was a conscious choice to be ahead of the curve and prepare for future work (and yeah, 35s too).
I view the gears as one of the best upgrades. You use them every second of every drive, and they make a 7k lb SUv with 35s drive like a go-kart.
They didn’t do anything positive for mileage, but it also didn’t get much worse as I piled on the weight and aero compromises.
I already had a steel rear with swing, and planned on adding the usual things over time. I didn’t want to lose drive ability as inevitably there is a lot of freeway before the trails. So it was a conscious choice to be ahead of the curve and prepare for future work (and yeah, 35s too).
I view the gears as one of the best upgrades. You use them every second of every drive, and they make a 7k lb SUv with 35s drive like a go-kart.
They didn’t do anything positive for mileage, but it also didn’t get much worse as I piled on the weight and aero compromises.
Just regeared myself with 4.88’s. Happy I did it but I also added front and rear lockers. I notice drive ability wise it’s better but not as great as expected. Off road with lockers, worth every penny. MPG’s are better. Just drive like a grandpa on the highway like me and do 65, or 60 according to the speedo.
Would you happen to have a list of the items you’d recommend picking up while swapping 3rds?Sure, we stock all those too.
No, more things like CV axle seals, FIPG, diff gasket, housing o-ring, hub seals, etc. Things you don't want to have to swap later because they get buggered upon disassembly or re-assembly.
I’ve got a tundra front front 3rd member and 100 series rear that I plan on installing at some point, though I do not know what extra items I should be considering adding.
turbo8
Supporting Vendor
Not sure how many miles you have on your 200, but when I changed my gears @250K, I also did the following:
Wheel bearings F/R
CVs F
All the seals F/R
Brake rotors/pads F/R
Drive shafts (originals were rebuilt and kept as spares)
What year is your truck? What size tires are you thinking of using? Are you going to tow a trailer?
Idaho Savage
GOLD Star
This is a dirty thread that will get me in trouble. I just moved to 35s in a pretty heavy 2021 and the highway performance blows.
Who would you guys trust do do this type of work? On the spectrum, is this a "Slee or Kurt only" project or my normal mechanic. Doesn't seem terrible but sure wouldn't want to F this up!
Who would you guys trust do do this type of work? On the spectrum, is this a "Slee or Kurt only" project or my normal mechanic. Doesn't seem terrible but sure wouldn't want to F this up!
I called a few places locally, after a few min talking to them you’ll know.
I also did rear wheel bearings at the same time, the bearings were more of a problem than the gears to find a shop that was familiar.
I’m in almost the same boat, heavy ‘21 with 34’s and tow.
The slightest up hill or headwind while towing and I’m deep into the tach. I don’t care about MPG’s but I don’t want to listen to sustained RPM’s of 4500 just to maintain 45mph in second.
turbo8
Supporting Vendor
Sounds like you need gears and a supercharger!
bloc
SILVER Star
No good tuning options for a supercharger on a 21.
And I’d be using Slee or cruiser outfitters or whoever they recommend now that Zuk is taking a break. These things need to go for 300k if they are to match the longevity of the rest of the vehicle. That also means I’d be looking at a ratio available in Genuine Toyota parts catalog. Objectively higher quality than aftermarket based on evidence during break-in.
And I’d be using Slee or cruiser outfitters or whoever they recommend now that Zuk is taking a break. These things need to go for 300k if they are to match the longevity of the rest of the vehicle. That also means I’d be looking at a ratio available in Genuine Toyota parts catalog. Objectively higher quality than aftermarket based on evidence during break-in.
For the 8-speed guys, the desired rear end ratio is going to be different. They start with a 3.307. The two or maybe 3 relevant ratios are 3.9s (+10%), 4.1s (+24%), and possibly 4.3s (+30%) for the seriously big tired guys. IMO, 3.9s would be the preferred re-gear for most, as that'll get back to better than factory gearing with even 36s.
Compared to 6-speed that starts with 3.9s, 4.3 (+10%), 4.88 (+25%), 5.29 (+35%).
4.3s on an 8-speed would be like dropping in 5.29s on a 6-speed.
I would say the 8-speed guys should be able to more easily source ratios and pumpkins. Either the factory front and rear pumpkins out of pre-2016 cruisers. Or the standard 4.1s found in 90% of tundras and sequoias. These would come with the necessary front housing to support aftermarket lockers as IIRC, the deck height of the 3rd member in the post 2016s were different, and not compatible with aftermarket lockers.
Compared to 6-speed that starts with 3.9s, 4.3 (+10%), 4.88 (+25%), 5.29 (+35%).
4.3s on an 8-speed would be like dropping in 5.29s on a 6-speed.
I would say the 8-speed guys should be able to more easily source ratios and pumpkins. Either the factory front and rear pumpkins out of pre-2016 cruisers. Or the standard 4.1s found in 90% of tundras and sequoias. These would come with the necessary front housing to support aftermarket lockers as IIRC, the deck height of the 3rd member in the post 2016s were different, and not compatible with aftermarket lockers.
bloc
SILVER Star
Yeah I didn’t detail that part. Both people asking are in newer 8-spd trucks that have good options for factory gears.
6spd will have to get gears from souq if they want to go lower than the 4.3s you outlined and stay factory quality.
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