The infamous H55F, as it pertains to an early FJ40 (1 piece t-case equipped thru 8/80')
The H55F will bolt directly to an F/2F/3F block, using a 4spd bellhousing. Some will require some very minor grinding on the index "ears", but overall it is a direct bolt up. Clutch, slave, etc are all the same, the front 1/2 of the H55F is identical to an H41/H42. This is where the similarities stop in regards to an early FJ40. The rear output on the H55F is always a 19 spline. Therein lies the issue. The 1 piece case ONLY has a 10 or 16 spline input gear option. Issue number two is the different bolt patterns between the two. So one is forced to update to a Split Transfer Case if they wish to install the H55F (T-cases found in 80-90' Land Cruisers).
Park Brake Issues:
The Split T-case found behind any US spec 60 series will NOT have a park brake option. Nor will the axle of an early thru 8/80' FJ40 have park brake provisions on the rear axle proper. So you have one of several options, this being the biggest issue in the swap.
1. Park Brake Kit for the Split T-case. Basically uses OEM parts from non-US and late model FJ40 applications to put a park brake drum and backing plate on the donor Split-Case. Parts alone can cost $400-750 and one will have to dismantle the case to install, so a rebuild kit ($200) should be considered.
2. Late model FJ40 or FJ60 Rear axle. My preferred method. Using an 8/80' or later FJ40 axle housing will get you cable actuate park brakes on the drum. Additionally you get bigger better drum brakes and single wheel cylinders that auto-adjust! FJ40 housings can be hard to find, but they are a 100% bolt in. FJ60 rear axles are widely available, but they will need perch/shock mount rework and you will gain ~3" additional WMS - WMS width out of the setup. Good for some, less than ideal for others.
3. Alternative brake setups: Electric or mechanical line-locks (not legal as a p-brake in many states). Rear disc brake upgrade using a caliper with p-brake capabilities (ie Caddy calipers).
Other Conversion Issues:
Driveline lengths need to be changed
Driveline patterns can be an issue
Speedo Cable
Park Brake Cable Length (if p-brake is put on Split T-case)
Crossmember relocation
Transmission crossmember fabrication
Caveats:
Not all H55F's have the input setup for an F series motor, those used behind an H Series diesel will, however those use behind a B series diesel will NOT and will require a new input shaft (~$250)... keep that in mind while shopping.
There are several different H55F's that were made, 85-85 & 85 & later. Differences are minor, its theorized that there may be slightly different ratios in some but I've never found hard proof of that. For reference all of the H55F's I've used were those made to go behind an F/H motor, however I've sold the input shaft to those converting and they did install fine.
Also, there is one tiny tad of evidence of an OEM Toyota 5spd that was mated to a 1 piece case... a single picture in a parts catalog of the combination. I've discussed it with several long time Cruiser experts, none have actually laid eyes upon one. Its possibly a non-US option that existed in the very tail end of the 70's or early, early 80's prior to the invent of the Split Transfer Case. (for info on split cases click here
Cruiser Outfitters Tech)
