Thread: D2 ZF Auto box - Bits therein.

Originally Posted by CU55TM Disco

Time for a 6hp conversion

And a 3L Lion engine. Oh and a Getrag MT82 box

Originally Posted by INter674

Mmmm ZF 6 speed has a bad reputation. ..yes😐??

I think mainly because the trans cooler fails on the 6 speed falcons filling the trans with coolant.

But if it can handle the power of a tricked up Barra, it'll hold all the td5 can throw!

Interesting. Curious tho, is there an adapter plate and controller to suit a D2?

Originally Posted by INter674

Mmmm ZF 6 speed has a bad reputation. ..yes😐??

Originally Posted by CU55TM Disco

I think mainly because the trans cooler fails on the 6 speed falcons filling the trans with coolant.

I’m not aware of a bad reputation for the ZF 6 speed transmission itself. I know the implementation in the Falcon had issues with the integrated automatic transmission cooler inside the radiator allowing coolant to enter the transmissions oil system when it failed - this caused issues and damaged boxes but wasn’t fault of the ZF product.
In the Disco 3 and 4 realm they seem to work well and hold up, especially when properly maintained (plenty of threads on what that involves in that section of the forum).

Originally Posted by John_D2

Interesting. Curious tho, is there an adapter plate and controller to suit a D2?

No, there is no kits available. Not even aware of anyone having successfully done it.


Regarding putting it into a Td5 I wonder how the gear ratios would compare - does it have a lower final drive to reduce highway RPM? Is first gear shorter? Or is it just the same overall spread from top to bottom but with more gears inbetween?

Originally Posted by twr7cx

Rick, he can't be looking too far. Ashcroft-Transmissions in the UK are still supplying them for around $3,000.00 AUD delivered including the core deposit, GST and import duties at the current exchange rate... I imagine that labour charges for the removal of the old and fitment of the new are less than $4-5,000.00...

Doesn't look like they list any of the individual parts mentioned for sale separately < Ashcroft Transmissions > but I wonder if they will/would supply those parts if they were directly engaged by an enquiry...

Hiya

Reputable xmission specialist, if he can't source reasonable priced replacement parts through his various supply chains, what do you reckon about average punter in here, or out there for that matter??? (Same bloke managed to find me the (only in Oz) set of BMW E30 diff bearings to suit my diff. Had to come in from WA.)

He did say he could get ZF stuff but price was excessive, plus a rear clutch of some sort. similar price?? that makes around $5-6K for bit/s plus GST, freight and labour. Don't reckon there is much change out of $8K. What is the current red book value of a D2?

You are talking about full transmission. Ashcroft are "rebuilding" them but no mention is made of new clutches etc. Just strip clean inspect and rebuild and test. No mention of no longer available "replacement" parts such as the critical clutches. Arguably if they look alright they are just re-installing them.

I will be happy to be contradicted. Would mean there isn't a ZF parts problem out there, and auto D2s will be around for many years to come :0) O/wise D2s will be constrained by the number of operational autos, or mod kits. :0(

Cheers

RF

Originally Posted by Rick Fischer

You are talking about full transmission. Ashcroft are "rebuilding" them but no mention is made of new clutches etc. Just strip clean inspect and rebuild and test. No mention of no longer available "replacement" parts such as the critical clutches. Arguably if they look alright they are just re-installing them.

I can’t comment particulars about what they’re company is doing. If you’d like further details I’m sure you can contact them and they’ll have a chat to you about it.

If it helps, their website offers the following:

A common problem with all ZF 4HP22/24 boxes is the failure of the oneway 'sprag' clutch. Once the cams in this one way sprag clutch 'flip' the unit will slip both ways resulting in the vehicle only pulling off with the shifter in position '1' not 'D' and driving OK when shifted up to position 2,3 and D until you stop then you need to pull it back to '1' to start off again. It is not feasible to change this unit in each rebuild as this one part is approx £ 400. By disassembling the 'sealed unit' we were able to examine the profile of the cams and understand how they work, from here the challenge was to find another cam from another type of autobox that would fit and had the correct profile to make the unit stronger by not allowing the cams to flip. After quite a lot of searching we found one, 're-cammed' some of these clutches and thoroughly tested them, we have not had one fail since. This is an example of how we are able to use our engineering background to understand a problem and cost effectively make the unit stronger without having to raise our prices.We have also recently invested £ 20,000 in a test machine. This machine allows us to do 2 things. Firstly once the valve body has been rebuilt we are able to fit it to a plate on the test rig and run the valve body through its cycle with 45 deg pre-heated oil to simulate as close as we can get 'real world conditions' The hydraulic valve bodies are run through manually by winding a valve to simulate the governor increasing in speed and various pressure gauges are monitored to see that the valve body is applying the correct clutches at the correct pressures. When testing the electronic ZF valve bodies once the solenoids are all tested this cycling procedure can initially be run through manually to check all is well then the computer can run up to 100 full run cycles going from 1st, 2nd, 3rd, 4th and lock up down to 1st again to ensure no valve are sticking and the solenoids are not failing when hot and working hard.

We are also able to fit a test plate to the autobox in place of the valve body and apply heated oil at pressure to check we have no leakage or pressure drop on any of the clutch packs.
This machine has enabled us to improve the quality of our boxes by identifying any potential faults or problems before the box reaches the customer.

All our boxes are fully rebuilt including the valve body and come complete with a rebuilt torque converter.

Ashcroft Transmissions

All our boxes come with a rebuilt torque converter which must be changed in conjunction with the autobox as they share the same oil circuit thus debris from a previous failure could contaminate a fresh autobox causing further problems if not changed.
How we rebuild them
When we rebuild a box, the unit is stripped down, washed in both Safety Kleen and hot wash tanks then the casings are shot blasted with glass bead, then painted. Once "Prepped" the stripped unit is sent to the build area in a plastic tub.

The autoboxes have a fixed set of new parts including friction plates, pump bush, filter, gaskets and seals, Once the parts are picked the first step in the build process is to lay the parts out on the bench for inspection, If they pass inspection they are used again, if not they go in the scrap bin.

Once the valve body is built it is put on our 'Hydratest' machine which cycles the valve body up to 100 start stop cycles to check all valves are operating correctly, it also checks all solenoids electronically to ensure they are also operating correctly. When the autobox is assembled we fit a test plate in place of the valve body and do a pressurised hydraulic leak test on all of the clutch packs to check they are correctly fitted and have no leaks. These two checks with the Hydratest machine help us to identify and potential problems before the box is sent out.

Once built the unit is stamped with a number and a spec sheet filled out giving us info on the unit specification, who built it, when it was built and exactly what parts were fitted.

Ashcroft Transmissions

It’s not meant to be reflective of your Reputable xmission specialist, but this a company that is only working with a few select models IOT provide specialist expertise on these only. It’s likely they know them better than other organisations that are working on a much wider spread of vehicles and models.

But my original point remains that there are ‘rebuilt’ transmissions available, for significantly less than your initial suggested figures, to keep the D2’s up and running.

COOL!

That info is now all out there. Should perhaps go into "good oil" :0)

cheers

RF

I wonder if we could fit the 8 speed....