Thread: ZF Auto can't take Toyota 1KZ Turbodiesel ??

Originally Posted by Blknight.aus

and on top of all that if you use the wrong torque converter for the power of the engine (in terms of peak torque, max rpms, max hp and how its all delivered curve wise) you can stress the auto more than it will like, couple to that a mal adjusted throttle pressure cable and im not surprised that hes killing autos, the tinyest bit of missalignment between the engine,TC and input of the TX is going to cause some big problems later on down the drive line.

If hes just bolting the TC to a flywheel (not a flex plate, theres a big thread on this elsewhere in the forum but trust me theres a difference) thats got its on inherent risks if its not micromillimeter accurate in its alignemnet. If a bit of grit has gotten itself into the box and gotten stuck somewhere where it can machine other parts out of spec thats going to shorten the life as well.

Theres a dozen reasons why an auto might die on an engine that it wasnt made for but as for it not being able to deal with the power output of the yota diesel, I wouldnt have thought that it was a fault of the box but something that was done incorrectly.

Spot on....

First of all I would like to thank everyone for your detailed replies. The big picture is now coming into focus.
1/The ZF boxes would almost certainly come from V8s. There are very few Diesel Disco Mk1s in Thailand.
2/I was not aware of any major differences in V8 and Diesel transmissions, other than size of torque converter (this is new to me).
3/Interestingly, "Ashcroft Transmissions UK" who specialise in rebuilding ZF units, recommend using the larger V8 torque converter in Diesels, as the smaller one is inclined to slip during "lock-up", especialy if the engine has been "tweeked"
4/Bangkok, with it's heat and traffick jams, is a sure killing field for auto boxes. My ZF had a spiked pipe cooler in front of the rad; I believe that this was totally inadequate for tropical climate. My Toyota uses a "rad" type cooler. There are 70 odd of these conversions, mainly in Bangkok, and they seem very reliable, despite the fact that the T/Cs are working hard due to 22% increase in gearing.
5/Based on experience, I believe that the increased gearing (overloading the T/C) is a major cause of the poor m.p.g., I used to operate an MF loader (similar to JC with T/C transmission. It would load all day in the field on 4or5 gallons of fuel (low gear work), but travelling on the road (high gear) it would rapidly empty the tank, and produce plumes of black smoke.
6/I am now considering replacing my Disco axles with Toyota, which will bring the gearing back to normal, and also provide FW front hubs. FUEL IS TOO DEAR TO WASTE, even @30Baht / litre
7/Used Toyota parts from Japan are plentiful and fairly cheap here (unlike LR parts!)
8/Incidently, the 1KZ-T motor has electronic fuel control, with air temp. and boost pressure sensors.
Cheers,
Joe

What method have you used to increase the gearing?

The gearing has been raised accidentaly as a result of mixing LR and Toyota components, which are not really compatible.
The LR Transfer Box has a 22% reduction (1.22:1) and drives through a 3.54:1 Differential.
The Toyota Transfer Box is direct drive (1:1) and Toyota Diffs normaly 4.1:1.
The end result is about the same.
I currently have a Toyota (part time 4wd) Transfer Box driving LR axles

The ultimate solution to my problem is to reinstate the original LR Transfer Box, but I am unable to find anyone here who can do a sustainable job.
I BELIEVE THAT THERE ARE MANY CAPABLE ENGINEERING SHOPS IN OZ.
MAYBE SOMEONE CAN SUPPLY A QUALITY CUSTOM MADE ADAPTOR SHAFT TO COUPLE THE TOYOTA AUTO-BOX TO THE L.R. TRANSFER BOX ?
Can the box flanges be redrilled, or is an adaptor plate necessary?
Cheers,
Joe

So its a Toyo engine and transfer but ZF Auto?
And your going to put Toyo diffs in it??

Ive got a great idea....
Sell it as land fill and just buy a Toyo............... your halfway there now

Originally Posted by sclarke

So its a Toyo engine and transfer but ZF Auto?
And your going to put Toyo diffs in it??

Ive got a great idea....
Sell it as land fill and just buy a Toyo............... your halfway there now

Always constructive advice when it comes to conversions steve

Originally Posted by rovercare

Always constructive advice when it comes to conversions steve

Yep, i'm open to conversions, but if the whole driveline will be Toyo, why keep the poorly built LR body???

Originally Posted by sclarke

Yep, i'm open to conversions, but if the whole driveline will be Toyo, why keep the poorly built LR body???

Why put Zebra stripes on your Defender??

Because you want to