Re-gear for H55 w/ 33s?

[LazarusTaxa]

Hey @LazarusTaxa I just came across this thread as I am contemplating 4.10 vs 4.56. As you know I'm in the midst of tossing a H55 in my rig that has 33" tires. Pretty much copying what you're doing because you're so cool.

One thing that I noticed here in Bend is that the elevation plays a large role in this discussion. My stock gears and 33" tires feel great in Seattle, not so great here in Bend.

I'm going to drive my rig for a bit both in Bend and in Seattle once it's all back together with the new trans and stock gears. But my initial thought is to go with 4.56 because 4.10 might not be enough at this altitude. I'm okay if my max speed is 65 mph.

Haha, i'm glad someone thinks I'm cool. My father in law has a 60 here in town that he just had an H55F put in and has 33" KO2s on it (so like 32s).. He did not regear.

It's fine on flats, no complaints there. But yeah, when we head up towards bachelor, it has a lot of trouble and slows down considerably. We took his 60 to get a Christmas tree and I want to say we were in 3rd doing like 40-45 going up past green gate (tiddlywinks trailhead).

I think 4.11s will be a good compromise between having some 1st gear to use in town and being able to climb hills.

 

[2mountainfish]

I lived at 4200ft when I did my swap to h55 with 33s and 4:10s and it did just fine. Now I live at 2200ft and it’s even better.

 

[Godwin]

H55F + 4.11s + 33s is a proven combination. What used to be a good source for 4.11s would be diffs from a FJ62 but those have become scarce. Alternatively you could use rear diffs from semi-floater 80 series axles. This are 4.10 geared but are direct drop ins. Like the FJ62 diffs may be hard to find without high mileage.

 

[77CruiserDog]

Thanks for the input @Godwin and @2mountainfish , would you say that 4.10s would be good even living at roughly 4000ft and regularly driving up to 6000ft?

I'm on the fence as either gearing would be the same investment but the 4.10s might not get me all the way to the sweet spot and that's why I was contemplating 4.56. The mountains we drive up and over are considerable... not quite Colorado but still.

 

[2mountainfish]

4:56s would probably keep you out of 3rd on some hills, but it will definitely raise your rpm at highway speeds. For me, I really like the ratios in the H55 better then the H42. At 60-70 mph in 5th it puts the rpms right in the sweet spot of the torque curve. Going from second to third is also a much better transition. With 4:56 gears, you will definitely not be using 1st on the street. It’s almost annoying low with 4:10s. I am willing to sacrifice on the hills a little to get the nice cruise in the flats. I use my rig off road but realistically I do more miles on road. Off road the 4:56s will shine in technical situations but I find the lower 1st and 2nd of the H55 very effective. A cheap way to test out 4:10s is buy a used third member from a FJ62, throw it in the rear, disconnect your from driveshaft and cruise it around. Hope this helps.

 

[LazarusTaxa]

@77CruiserDog, you're welcome to drive mine when I get it put back together. But realistically, you'll probably beat me to that point.

 

[Godwin]

Thanks for the input @Godwin and @2mountainfish , would you say that 4.10s would be good even living at roughly 4000ft and regularly driving up to 6000ft?

I'm on the fence as either gearing would be the same investment but the 4.10s might not get me all the way to the sweet spot and that's why I was contemplating 4.56. The mountains we drive up and over are considerable... not quite Colorado but still.

I don't drive in mountains often enough to answer the question of 4.11 or 4.56.

 

[goped]

I don't drive in mountains often enough to answer the question of 4.11 or 4.56.

I'm curious what you went with? I have 33s and stock everything. Would 4.56 be better for a 4 speed and 33s? I have to drive up hills where I live. I also would like to go at least 70 mph on the highway.

 

[Godwin]

I'm curious what you went with? I have 33s and stock everything. Would 4.56 be better for a 4 speed and 33s? I have to drive up hills where I live. I also would like to go at least 70 mph on the highway.

2F + H55F + 4.11diffs + 255/85/16 Geolanders (essentially a 33" tall tire). On flat ground I can run 70 mph with this setup, hills will need to shift down and it a long hill often to 3rd at 45+. The 2F is tired with 300k miles on a rebuild.

4.56, a 4 speed, and 33s would have the motor running ca. 3000 at 70, maybe higher. With my combination the motor is turning about 2500+ at 70.

 

[goped]

So stock 4 speed with 33s and 4.56 is safe to drive 70mph at around 3000 rpm for some long stretches? I appreciate the help. Thanks

 

[FJ62DadWagon]

I thought I had replied on this thread with an update on my 4.56s, I see now that I never did.

I have a prior post after regearing to 4.56s with an H55F in my FJ62 w/ 3FE.

@goped I imagine H42 with 33s and 4.56s would be a bit over 3k rpm and keep you off the highways. I was at 2900 with an H55.

It performed well in the mountains but the gearing felt a little too low at 70mph. Long Texas highway portions of our trips were a challenge with 65 being much slower than most drivers.

I rebuilt my tcase in 2023 and opted for 10% OD gears. This put my ratio exactly back to the same as when I had 4.11s without regearing both diffs. I’m much happier with the combo and would recommend H55F, 33” tires and 4.11 gears as the best all around balance.

 

[goped]

Great. I appreciate your input. Im going with the 4.11s since I will do more onroad driving. I should hopefully notice a difference going uphill than stock 3.73s. Thank you

 

[CruiserTrash]

2F + 33s + stock t-case. I put 4.11 gears from an FJ62 into my FJ60 and it’s the right balance. In my scenario I’d suffer on the highway with 4.56 - probably max speed of 55-60mph to comfortably keep the motor below 3000, which is it’s happy cruising area.

 

[Skreddy]

Great. I appreciate your input. Im going with the 4.11s since I will do more onroad driving. I should hopefully notice a difference going uphill than stock 3.73s. Thank you

What rpm do you typically shift at? I think this plays a big part in people saying they can’t pull hills, etc. Mine is an H55, Kenda Klevar 33’s and stock 3.7’s. I can run 75 mph all day. Big hills, ya, downshift to 4th. Really big mountain passes, I might be in 3rd at the top doing 50 mph but I’m not sure I’d be any better with 4.11’s in 4th as I’d be lower in the powerband. I shift at 3000 rpm or even 3500 if I’m at a hill. I’ve debated on 4.11’s but for 95% of my use, I can downshift a lot for that cost.
I’m in Spokane, WA with routine trips into Idaho and Montana over the mountains.

 

[bronco loco]

My Fj62 came with axle K082 which has 4:10 from the factory, they were replaced with 4:56 with the 285/75r16. This truck travels from sea level to 16K feet above sea level, any given day, thanks to the Andes Mountains.