In Conclusion then:
If you are going to do this as a DIY project and you don’t have a lot of time on your hands, then source your gearbox/ tcase from a 70 series and get everything from the donor vehicle, levers, lever rubbers and frame, wiring loom and all clutch components. You don’t need the cross member.
The reason you want a 70 gearbox and transfer case is the part time transfer case. You retain part time 4x4 without very expensive modifications, the positioning of the prof shaft flanges are in almost exactly the same place as the split transfer case and, in my case at least, the bolt patterns were exactly the same. (Donor was a FZ79 pick-up.) And the levers are in a far better place than the levers on a full time transfer case would be. They are in fact only 80mm further forward and the gear stick bends back, so the knob is in the same place as the R151.
View attachment 1910620
You also need a HD bellhousing which can be a bitch to find or expensive from Toyota. I would be very hesitant to start the project unless you have sorted the bell housing.
The HZ’s clutch slave and rod were bolt on and did not even require bleeding.
Cutting and hacking:
As an old Land Rover man, I have had it with conversions, and regard this as a swap. The only hacking was on the tunnel to accommodate the new position of the levers. But, this cover on the tunnel was spot welded on so that Yoyota could use the same pan for the Hzzz, HD, Fz and V8, and the FZ cover is available, and on order . (Watch this space)
I also hacked the gear lever tower off the transfer case as it seemed to a little high and I worried about clearance, but probably un-necessary. (See concerns further down.)
The carpet needed the same hacking at the metal work below.
Left over bits and extra parts necessary:
View attachment 1910621
Yes, the nice yellow cross member is from the FZ donor, I lovingly cleaned and painted it, and then tried to fit it. Fail, and not necessary as the HZ accommodated the H150 mount. The pickup chassis is probably essentially the same, but the cross member outrigger mounts are on the outside of the chassis, and on the inside on the 76 wagon. They are both flat on the top surface, so the mount is where it is supposed to be in either case. (See concerns below)
I will probably get shot for not doing the HZ’s oil seal while I was in there, but even at 250K it looked so happy and dry and clean, with original Toyota gunk (FIPG) on the pan and seal holder, I just had to leave it alone.
Clutch disks depend on which gear box you get. The H150 and 151 are supposed to have different input shafts but this is not the case. The Fz79 in this case had a H150 with the same input shaft which everybody thinks should be on a H151 ( 32mm 14course spline) And a 275mm clutch, not the 300mm found on the 80’s and 100’s and possibly other pickups. No matter, all the parts are
available, but you do need to look around. (PM me for part numbers if you need to). That’s also why I suggested getting all the parts from the donor car.
Without actually counting the turns ratio, I have yet to find a way to tell which box is which. And no, I do not have a Frankenstein box it’s how the Fz 79 (front coil) pick up rolled out.
Clutch cover from the HZ is retained. The Fz clutch bearing can be used but you lose travel so probably not a good idea, rather get an HD bearing which is about 8mm longer (thicker). Hz (r151) bearing cannot be used, but the fork can.
Spigot bearing must be changed to one with a 15mm ID.
Small concerns:
The engine now seems to tilt backwards a bit. ( or a bit more) It may just be my imagination, and I did not check it before hand, so I am not going to throw a wobbly just yet. I confirmed an engine back ward tilt of 3 degrees by using jacks to level the car, using the bottom of the front doors as a reference for level. As mentioned, this may be normal. I used the iPhone as a level checking device so it’s not engineering standard, but good enough to confirm. Could it be that the HD and Fz engines which use these gearboxes sit a little lower in the frame? I can lift the back of the gear box and fit a spacer under the gearbox mount, but only about 6mm (¼”) before I run out of thread. And I don’t want to do this unless I know I have to.
The H150, with 230K on it, is a little noisy when cold but quietens down to almost nothing when warm. I am talking about when the vehicle is standing and idling. If you engage the clutch, the noise goes away, but if this is repeated once warm, you can hardly hear the box. The first time, I thought that it was the oil pump priming, but it does it whenever it starts from cold. My experience is only with H55F’s and the R151, so gearboxes with oil pumps are new to me. Is this normal for an old box during warm up. I have also used very basic oil, nothing special. ??
Conclusion:
I am very happy with the 200 odd KM’s of test drive so far and the higher overdrive ratio has not become apparent yet, but I don’t have a rev counter and have not done long fast open roads yet. It shifts as well as the R151 but does need to warm up and it does not enjoy being rushed between gears, but it’s a cruiser, what’s the hurry. I can definitely live with this box, and am willing to put the old R151 on the market even at this early stage.
Feel free to PM if you have any questions.
