Thread: TD6 Manual Gearbox Conversion... Is it possible???

Thanks Gavin.

Good to see you still recomend them. Great service by the sound of it. Hope all your problems are fixed soon. & touch wood I dont have to use their services.

Would be interested in what parts went into you auto & how much more torque it can now handle.

Some of the problems with going to a manual are .
1 Adapting gearbox to motor
2 Adapting transfer case to gearbox
3 Getting all to computors to talk to one another.
But then you know all this already.

Gary

Originally Posted by 33chinacars

3 Getting all to computors to talk to one another.

Gary

This is the bit I'm most worried about. Adapting the gearbox at each end can be done, even if there is engineering hurdles to overcome. What worries me is what the electronics are going to think about not having a transmission computer to talk to any more...

That's one of the reasons I'm starting on this now, and not when I might need it again.

As for what's been done to the box - quite a bit, but most of the mods he does are designed to give the box a longer life - that may translate into being capable of more power, but not sure. The valve body now has new style valves that will seal inside worn bores for longer. One set of frictions in it have come out of a Commodore box - they are stronger, but need machining to fit. I believe the torque converter is rebuilt better and stronger - this is one of the weak areas, something in there rips itself apart and ends up trashing the whole box.

Will see how it goes for a while before I think about chipping the engine, maybe after the first fluid and filter change to see how it looks inside...

Gav

Thanks Gav

Looking forward to more updates

Gary

If it helps any I remember an old article comparing manual trannies for blown v8/turbo sixes (in either wheels or street machine) and the supra manual was a clear winner over the gm/ford options with far larger bearings/stronger gears and able to handle far more power. I cant remember what clutch etc they used but look at what they are doing in the jap turbo scene as there is a huge amount of development there with ,massive power outputs.

Thanks Frantic, I hadn't thought of the Supra box - they are a highly regarded box. I'll do a bit of research on them

Cheers - Gav

Well, after Frantic posted about the Supra box, I started doing a bit more research, and went slightly off tangent, but I may have found a box that would work.

Rather than modify a 2wd box, I got to thinking what other manufacturers use in thier 4wd's. Dare I say it, but Toyota have a 4wd box that may work...

I was looking at the R151F box that was used in the 100 series Land Crusiers. 5 speed box, with ratios that would work.

1st - 4.313:1 (very low compared to the auto)
2nd - 2.330:1
3rd - 1.436:1
4th - 1.000:1
5th - 0.836:1

Strength wise won't be an issue. Although originally used behind the 1HZ diesel, which is a bit down on Hp and Torque than the RR TD6, it looks like it was also used behind the 1HD-FTE which was good for 201Hp and 317 ft-lb of torque, so I don't see any issues here, even if I end up chipping the engine

It looks like this...






I haven't been able to find dimensions for the box yet - still looking, but it looks to be in the ballpark. I am hoping it is a bit shorter thn the auto combination, to allow for an adaptor plate at each end, but that is still to be seen.

Price wise they seem to go for between $800 (for a medium milage second hand unit) to $2,900 for a brand new unit with Toyota factory warranty - not bad really, and I think I should be able to get a good second hand unit, or a reco for around the $1,500 to $2,000 mark, so right on the money there. Availability is very good, as there are tonnes of these in the country, and plently of companies that offer both the boxes and parts.

If anyone knows of, or can find specs/drawings for this box, it would be greatly appreciated. If it dimensionally ok, that may be the first part of the puzzle in place.

Cheers - Gav

h150 you would use, definately not an r151

h150 is what is behind the 1HD FTE

Have I missed something - why not a BMW box and bell housing that bolts straight up to your engine as was discussed originally.

If you are going to use a toyota box box then why not a landie box - the manual six speed out of a D3 or even an R380 - if the toyota box can handle the torque of your engine then so will an R380.

Garry