Outer Limits 4x4 Board

hello all.
i have a 45,000k old h55 in my 75 cruiser ute wich is about to get a huge power upgrade from a 300hp 308 v8. just wanting to know how long i can expect this gearbox to hold together?
also when it does give up i'd like to put a t700 in it's place does anyone make an adapter from trimatic pattern motor to turbo auto?

cheers

anyone know as i've allready done a search

known 2 wrote:anyone know as i've allready done a search

We dropped a hot 350 chev in front of one. It took plenty of abuse, never broke.

I got a 5speed from a 2H behind a 6.2 V8 Diesel... no dramas what so ever..... (touch wood!!! ) And it's not like I go easy on it either.

Usually the clutch will go before the g'box anyway I reckon.....

ah thats good news.
the gearbox guys reckon the h55 is more resiliant that the h151 allthough it's smaller in size.

known 2 wrote:ah thats good news.
the gearbox guys reckon the h55 is more resiliant that the h151 allthough it's smaller in size.

Buggered if I know what model it is... just a 5 speed behind an 84 HJ60 originally.

I don't know if its the same as the gearbox that was behind my 3F but I was told that the weak link in the gearbox was 5th gear. Even if u have the torque to pull big loads up hills on the highway, it might be good to gear down. Also, the gearbox isn't designed to spin up to 6000rpm, even if the new engine can.

nah my motor is only guna rev to 5500rpm and i rarely ever tow anything.

my old work mate had a hot 307 with 350 internals pushing around 450hp in his hilux, put a h55 behind it and still going strong

Theh55 in your 75...if u had a 1hz infront 1990+ had issues with the transfer input shaft spline....the box itself is strong....you can get aftermarket gears that are wider and take the place of the pto gear...i dispute the h150 being weaker....more breakages on h55's than h150's

mine is pre 1990 i think it had 3 boxes so maybe. i hope it hols up lets me modifie other things.

Last of the 75 steel grills are the strongest of the h55...you need to consider where the new motors power band is...being v8, it will rev but mostly like 2000-3500.i dont think you could go past using the h150 because the ratios are closer in spacing, meaning changes at 3500 will land you back in the 2000 range....first gear comparison has the h55 at 4.88 and h150 at 4.5 and the transfer has 1.9 h55 and 2.45 h150 low range ..the h150 came out in the fzj75, so spares are available from Toyota, they do fit, and are mega strong...the latest t/d 79 has one behind the diesel, and the 4.5 and v8 100 also use the h150f
Best to decide now, as the adapter will be different...yes more work and time, but resulting in a better package...pm Tobie who has a hdft in a 75 with h150, the hdft killed the h55... must be others...

g'day Known2

andrew is right, i have a hdft in my 75x and went through 3/ h55 before i changed over to a h150

2 of the h55 were rebuilt and had less than 20 000 klm on them when they shit em selves

the bottom bearing below the main shaft just disengerated

not sure if it is the power or the tourque or the way i drive

i use the ute for a lot of heavy towing and heavy work

i also went through a h55 when i had the standard 1hz with aftermrket turbo

a mate of mine had a 79x with aftermarket turbo and has already been through 1 gearbox.

had the h150 in the ute for about 12 months and had no dramas so far except that it needs a bearing kit in it, should have done it before i put it in

easy to put in bolt straight up, needed a new crossmember, shorten back tailshaft, legnthen front, new floor cover plate from a petrol 75x and also the transfer lever assembly from either a petrol 75x or a hdj79x i got everything needed from a hdj79x and the box from a 1hz 80x

thanx for the input guys. but when my box blows as it only has 20.000k's on it i'm guna use a t700 built tough and reduction gearing in the transfer.

r the standard transfers strong enough or should i up grade to gq stuff

Your chances of having trouble with the t700 are great...greater than the h55 they blow in commodores at 130000kms....put all that torque through it constantly pulling the cruisers weight, and you have a recipe for disaster...sorry mate, just telling it how it is....it would be better to t400 it and run 3.7's and transfer gears.

bugger what kind of 4spd will stand up to it then
i don't realy want a 3spd unless i have to.

cruiser auto will stand it...the older ones are hydraulic in the 60 and the 3f and first of the 1hdt 80 series...called an a442. It would cost 2000 plus to mod the 700 to take the power, and then it would still be weak compared to one of these...they dont like revvy motors...front seals pop out of them yada yada....mate had one with corvette converter and shift kit in a std 304 Torana and he blew it...there is a 5 speed on ebay at the moment that came from a 1fzfe....$500

i was waiting for someone to say cruiser auto.

i know there strong but they r so expensive. might have to settle for a 3spd

ebay auction number 320106763319

anyone know how much power a cruiser auto saps from ur motor and r shift kits and manual valves available for them.??

The h55 will handle a hell of a lot of power and abuse, Ive seen it first hand. My cousin built a 40 series tray from the ground up with a 650 hp supercharged chev didnt go to bad at all until he blew the motor and gear box up. Rebuilt the motor again then put an auto behind it. Great little gear boxes, just dont abuse the s@#% out them like he did.

known 2 wrote:i was waiting for someone to say cruiser auto.

i know there strong but they r so expensive. might have to settle for a 3spd

my old man has a cruiser auto behind a 6.5L has been in there for a few yrs.

Nat84 wrote:

known 2 wrote:i was waiting for someone to say cruiser auto.

i know there strong but they r so expensive. might have to settle for a 3spd

my old man has a 62 cruiser auto behind a 6.5L has been in there for yrs