H55: Strong Enough for Full Size Vehicles?

[mathamattox]

I am contemplating an H55 swap into my 80 series cruiser and am in need of some opinions.

I know there are plenty of H55s in 40 and 60 series cruisers so I believe that yall can provide some good insight. If I were to complete this swap it would be in a daily driver. Any issues with using the H55 in a daily driver?

An 80 series may tip the scales at 5700 pounds or more. I would imagine that a built 60 series would be similar. And, although my 1FZ-FE engine is stock, it may not be in the future and right now supposedly produces 275 ft-lbf of torque. So, will the H55 hold up to a heavy vehicle and engine that may someday make good HP numbers? Along that same line, what was the H55 originally offered in? This can be a good indicator of its designed strength.

I have some other questions but I want this thread to address the strength of the trans. I will start another thread for questions on another subject.

Thanks,

Jonathan

 

[D'Animal]

I believe they put the H55 in the Troopy.

You really cannot get much more full size than a Troopy.

 

[Cruiserdrew]

How are you going to adapt it to the motor? Cool swap.

I believe the 80s overseas came with the H151 5 speed, so those parts are at least available.

It might be marginally easier to do a v-8 swap + NV4500 + split case.

Good luck and keep us posted.

 

[Bryan062087]

I second that. How are you going to fit the h55f on a 1fz?? Very interested to know if that is possible.

 

[mathamattox]

Overseas 80s came with the H151 5 speed. The reason I do not like this trans is the first gear of only 4.08:1 and the overdrive of only .88:1. The H55 bests the H151 in both the lowest and highest gears. The NV4500 is still and option but its 5.61:1 first gear makes it more like a 4 speed with a granny gear. The H55 has a first gear thats a little more in the middle groud where its low enough for offroad use but not so low that its impractical for road use.

As far as adapting the trans to the engine, I am thinking an adapter plate between the bellhousing and trans. Bellhousing would be a stock 80 series.

I would also like to put in an underdrive box, like a Klune-V, and then use the stock 80 series full time transfer case. I believe the Klune-V will bolt up to the back of stock 60 series trans with an adapter, so if the H55 will bolt in place of the stock 4 speed, then it stands to reason there is a good chance a Klune-V will bolt up to the back of an H55. After that a custom adapter would most likely be needed to the H2FA transfer case.

 

[GLTHFJ60]

Overseas 80s came with the H151 5 speed. The reason I do not like this trans is the first gear of only 4.08:1 and the overdrive of only .88:1. The H55 bests the H151 in both the lowest and highest gears. The NV4500 is still and option but its 5.61:1 first gear makes it more like a 4 speed with a granny gear. The H55 has a first gear thats a little more in the middle groud where its low enough for offroad use but not so low that its impractical for road use.

As far as adapting the trans to the engine, I am thinking an adapter plate between the bellhousing and trans. Bellhousing would be a stock 80 series.

I would also like to put in an underdrive box, like a Klune-V, and then use the stock 80 series full time transfer case. I believe the Klune-V will bolt up to the back of stock 60 series trans with an adapter, so if the H55 will bolt in place of the stock 4 speed, then it stands to reason there is a good chance a Klune-V will bolt up to the back of an H55. After that a custom adapter would most likely be needed to the H2FA transfer case.

I agree that the Klune-V should bolt up, but take into account that the 5th gear has special oiling provisions in the split case that are not necessary for the H42. That said, try it!

 

[mathamattox]

So who's got an H55 behind a stroked V8 in a heavy rig that rock crawls and can attest to its strength (or lack of if thats the case)?

 

[gifu]

i abused an H55F behind a small block on my FJ60. Only put about 30K miles on it before selling, though 8 years later the current owner contacted me and it seems to still be going. That being said, my friend killed his behind a 12HT, with only about 150K miles on it.

What about an H150? It has a 4.6:1 first gear, and it will bolt up to the 1FZ and the HF2 transfercase. The H55F will not bolt up to either. AND, to make it even more difficult, the H55F stick is about 8" further forward then an H150 or H151... this would put the stick nearly under the dash.

 

[Tapage]

After drive 60 series with H55F, 80 series with H151 and another with H151 I would said the H55F it's the best combo ever .. and the BF1A t-case too ..

the problem that I saw it's the distance in the 80 series .. seen a compromised lower dash in this swap .. due to shorter bellhousing in the H55F compared to H150 and H151 ..

Another thing to considere if you are talking about big tow .. it's the H55F have a 275mm clutch and the H151 300mm clutch ..

I do 300mm isuzu clutch in mine H150 .. but still miss the 5th from my H55f .. in the H150

 

[roscoFJ73]

So, will the H55 hold up to a heavy vehicle and engine that may someday make good HP numbers? Along that same line, what was the H55 originally offered in? This can be a good indicator of its designed strength.


Thanks,

Jonathan
[/SIZE]

They will pull heavy loads for 250000 miles as long as the oil is changed and they are not hurried through the gears.
The 1st and 2nd synchroes are the 1st things to go
Likewise ,dumping the clutch also kills them.
The main reason they stopped using them is that soccer mums dont like the long throw on the gearstick and the clunkiness.
The H150/151 have slicker,shorter shifts.
The H150 had a few synchro and bearing issues in the early model 80 series

All the heavy duty 7* series and 60 series and some of the 40 series had them from 83ish till 98 in oz
The Coaster and Dyna also used variants of that gearbox but they also used gearboxes similar to the H150/151

 

[mathamattox]

Thanks for the opinions so far! These are some good insights.

I guess explaining a little more what I want would help out though. I am looking for a trans that will give me the best on road driving experience. Particularly, I am looking for better acceleration. My auto has a measly 2.85:1 first gear and even an upgrade to the not all that low 4.08:1 first gear of the H151 would be a vast improvement I imagine. I am not as concerned about a super low gear for offroad because as I said earlier I would love to put in a Klune-V or other underdrive unit.

For simplicity the H151 would be unbeatable because I could use all stock parts for the swap until I got back to the underdrive. An H150 sounds like it could be a possibility but I am not sure they were ever offered behind the 1FZ-FE. I think they may have been offered behind the 3FE in the 91 and 92 80 series.

It sounds like the H55 is a good trans but with some swapability problems. I still have some more homework to do to determine what seems like the trans with the best combination of gears and ease of swapping.

 

[Cruiserdrew]

I don't think the swap you want is possible at all. There are no existing compatible bellhousings, so unless you are designing one, and a custom flywheel, it isn't going to happen.

Here are things you could do:
1-Leave it alone
2-SBC/NV4500/Splitcase
3-3FE/H55f/splitcase
4-SBC/NV4500/Np203/Split case

Remember that the 80 series has the gas tank in a bad place for almost any swap that involves making the drivetrain longer, so Klunes and other range boxes don't really fit.

Of your options, if you are not willing to leave it alone, I think the SBC/NV4500/Split case would be the most satisfactory overall, but the option of finding an H151 and all of it's associated parts and running that would be good too. I've driven a 5 speed 80 series from Venezuela and it is pretty nice and a smooth shifting tranny.

I've also thought about getting an early 80 with the 3FE and putting an H55f behind that. You give up a lot of power and drivability, but it would work and be pretty nice.

Keep us informed what you do.

 

[mathamattox]

I do have the ability to make custom adapters. That does not mean that I want to do things the hard way either. The H151 would be far easier just because you can use OEM flywheel, clutch, TO bearing, slave cylinder, bellhousing, etc.

If I were to use any combination I have suggested so far it would involve at least 1 custom adapter.

The point about the length of drivetrain is also a good one. I believe that you might could fit a Klune-V at 6.5" length because you have quite a bit of room behind the center of the transfer case. I think the tightest fit may be between the gas tank and the speed sensor on the rear ouput of the transfer case. Fortunately the Klune-V is made so that it can be clocked in 9 degree increments so it can be clocked down for better clearance.

 

[Tapage]

For simplicity the H151 would be unbeatable because I could use all stock parts for the swap until I got back to the underdrive. An H150 sounds like it could be a possibility but I am not sure they were ever offered behind the 1FZ-FE..

Not .. never the H150 where offered behing 1FZ-FE .. but was in the 80 series behind the 1HZ ... that share the same bolt pathern as same as 1FZ-FE .. so with the right parts it will be bolt on .. ( izusu clutch if you wanna keep the 300mm clutch )

The hH55F aren't that hard at all coz also where offered behind the 1HZ .. same situation explined above .. just some crossmember fab .. and done.

 

[Bryan062087]

So the 1hz h55f will bolt up to a 1fz?

 

[Tapage]

So the 1hz h55f will bolt up to a 1fz?

yes sr.. the only problem that you will need to handle it's the flywheel/clutch issue ..

Edit: with the right bellhousing

 

[gifu]

yes sr.. the only problem that you will need to handle it's the flywheel/clutch issue ..

Edit: with the right bellhousing

i think the 1FZ came in some of the smaller 70 series, bolted to the H55F? You would also need the matching (length/spline) input shaft from that set-up.