H55F has cross cut gears or straight cut gears ???

[cahilc]

Compared to a H41 4-speed tranny ? Curious if the H41 would be the more durable solution for 4x4'ing as opposed to the H55F.

Need to do a clutch job, output bearing and ??? soon for my H41 and figured I'd check $$$ to swap in a H55F.

Durability is my main concern.

Cheers,
Cahil

 

[photogod]

The H41 was used in the US (for what reason we will never know) and the H55 in most other countries. The gears are cut the same. First gear a bit lower and a great fifth gear. The first gear is really nice with larger tires. If you have the dollars I would really consider the H55. I have really liked it since I put one in. As far as a clutch, I would resurface the fly wheel, new rear seal, new release bearing, new clutch disc, grease the release fork and hub, push rod, clutch disc spline and inside groove of the release bearing as well as the front and torque to specs. Let 'er rip. My .02

 

[HZJ60 Guy]

Good Lord where was the sanity at when they decided not to bring in the H55?

Was it that there was a limited supply, and that the scumy Americans werent going to get the good stuff?




TB

 

[60wag]

Actually the H42 is the common US 4 speed. The H41 is a rare 4 speed with lower 1st, 2nd and 3rd gears than the H42. The story I read somewhere regarding the higher 1st gear was that it improved on road driveability - a big plus for the US market. Now why it wasn't a 5 speed? I have no idea.

 

[cahilc]

How about durability ? Is the H41/42 the same weight and case size as the H55F ? Which one is more durable for hard core 4 wheeling ?

Cheers,
Cahil

 

[photogod]

There is no mention of the H42 in the Toyota manuals only the 41 and 55. That is where I gleened my info from. As for case size, and size does matter, the case from the 55 to the 41 is the same but the internals are different because of the 5th gear and associated forks and shafts thereby adding to the weight. How much, I have no idea but the weight is worth it. There is most likely no difference in durability, after all it is Toyota.

 

[cahilc]

photogod,

Thanks bunches for the info !

Cahil

 

[cruiser_guy]

I'm told that the H41/H42 are a more durable tranny if that is your over riding concern. Knowing that, I still went with the H55 in my 'Cruiser, swapping out an H42 in the process. I like the taller gearing in 5th for the highway.
Those who are heavily into off road will go with the H41 swap to get lower ranges on the other gears, even though the H55 also has lower gearing in 1st than the H42.

 

[cahilc]

H41/H42 are a more durable tranny ...

Thank you cruiser_guy, great info !!!

Cheers,
Cahil

P.S. If I want lower gearing in the furture I'll throw in a Toy Box !

 

[OlympiaFJ60]

Compared H55F has cross cut gears or straight cut gears ???

The only straight cut gears are going to be the reverse gear and reverse idler gear. All others are "cross cut".

Brandon
Olympia, WA

 

[cahilc]

Thanks OlympiaFJ60 !

My concensus is that I'm gonna stick with my stock 4-speed. Durability is my main issue. My truck is a daily driver but at least twice a month sometimes more I'm into some serious 4 wheeling. Looks like a 4 speed rebuild, output bearing, and new clutch in my immediate future. At least this way I can pop in a Marliun Toy Box if I ever win teh lottery !!!

Cahil

P.S. Cross cut gears are many times stronger than straight cut too. Garage Queen trucks prefer straight cut to reduce noise but sacrifice durability.

 

[60wag]

I thought that helical cut (cross cut?) gears reduced noise but also reduced contact area - lower strength. Straight cut gears are cheaper to make, have larger contact area so are stronger, but whine a lot (like reverse).

 

[VTCruiser]

I understand that helical gears reduce noise and are theoretically a little stronger (more contact area), however, the "cross-cut" design is less efficient in power flow creating lateral force. Race/truck transmissions that are rebuilt more often prefer straight cut for both the more direct power flow efficiency and cheaper production costs.

As a daily driver i would opt for a 5-speed for the sake of fuel mileage. I would say the strength differences are negligible.

 

[Cascade Cruiser]

Spur (straight cut) gears are more noisy due to impacts between gear teeth. As a rule, helical gears provide constant contact between gear teeth, eliminating impact loads and increasing strength and durability. Probably a mute point because it sounds like both transmissions are cut the same.

 

[bad_religion_au]

my understanding is the h55f is longer (got told i'd have to redo my driveshafts if i did one), but that extra length may be in the trans case.... also the 5th gear in them is a weak point, especially 5th gear syncro's (generally in aust, the type of long range touring these gearboxes saw made them spend long times in 5th and the owners wouldn't clutch into 5th, causing the prob)

 

[photogod]

The 55 is longer if you have a pre 4/85 LC because of the trans change made there. Anything after that is a direct swap.