Thread: Discovery 2 transmission remap

Ahh. Thanks for the advice.
I have not been towing in 3rd, but D.
She seems to tow ok, but has to be close to 90km/h before she will lock up, then ease off the throttle. Soon enough, I catch up with Grandma doing 80 on the nose and auto drops back. Loose momentum. Repeat.
I will try 3rd and am definitely planning on mods to make her the tow vehicle she was destined to be.
This forum has invaluable info. I have been reading up for the last eight hours straight. Lol.

Hi guys,

I'll probably be able to start supplying stuff shortly.

I've recently driven a couple of non tuned engines with non tuned autos.... Oh my... That gave me a decent kick in the pants to get moving!


Part of the issue is it's a lot more work than tuning a NNN ECU, which is so quick and easy, where you can simply reflash, the chip on the TCU has to desoldered, new chip sourced and flashed, soldered back on then tested in case there's a bad pad or chip or other issue.

And then there's the issue of the actual tuning and getting that right.

I'm somewhat time poor and have been for a couple years, but if I get organised better, I should be able to get into it!

In the meantime, anyone towing needs to make sure they can do so locked up, I really think the extra heat_is_a_killer, and if you realise your converter is slipping when locked, that'd be a great sign to rebuild while you still have something that can be.

Other than that...

Thanks for your patience!!


Cheers
James

I put the V8 transmission control unit back in this arvo to see how it goes with the V8 torque converter and it is a nice improvement against when I was running the V8 transmission control unit with the Td5 torque converter.

That would be because the shift and lockup revs are now matched to the slip/stall of the V8 converter as factory intended I guess.

Unfortunately back to the 'over sensitive' kickdown when giving it a bit, but the upshift and early converter lockup on mild throttle is like I would expect the V8 drivers enjoy.

A lot of Td5 owners out there with performance fuel tunes would be so much better off with a V8 torque converter and a tuned transmission controller. (and I will add in also a variable nozzle turbo)

Having the slippery Td5 torque converter so the stock tune can rubber band its way up to speed towing a load was a bad decision in my never humble opinion, they should have used the V8 torque converter with a suitable ecu tune and tcu tune to suit the diesel characteristics (and put in a bloody VNT like other manufacturers were doing from back then)

Originally Posted by shack

Hi guys,

I'll probably be able to start supplying stuff shortly.

I've recently driven a couple of non tuned engines with non tuned autos.... Oh my... That gave me a decent kick in the pants to get moving!


Thanks for your patience!!


Cheers
James

Gday James,

Is this a service you are still offering??

Originally Posted by CU55TM Disco

Gday James,

Is this a service you are still offering??

Well yes.. but I don't know about the "still"!

I'm so busy with normal work this has to take a back seat.

When I started to look at tuning the TCU I just thought "wouldn't it be amazing if I could find the way to change lockup speed.

I managed that and you'd think I'd be happy.. But no.

Next was the warm-up routines.

Next was all the shift points, then a heap of low range stuff to use the torque converter better off road, then I realised that all old school (and most of the new school) remaps were running the wrong line pressure in the box and likely destroying torque converters (sound familiar?....Not suggesting I can stop this by any means, but I think I can certainly help negate accelerated decline with remapped motors).

Then I also realised on "big" tunes there was an issue with shift de-torque amounts so gear shifts were neither smooth nor calibrated correctly time wise.

Then came the fault codes to enable or disable as required for certain applications.

Then the uphill/towing adaptions.

And then why using the V8 TCU has a tendency to destroy the box through excess slipping.

I guess re reading through that I've got a bit sorted, but there always seems to be another hill in the distance as soon as you crest the current one.

So yes, I "still" offer this service, but it's very dependent on my time and your level of patience!

Originally Posted by shack

And then why using the V8 TCU has a tendency to destroy the box through excess slipping

Are you referring to V8 TCU with V8 Torque converter conversion or with Td5 original converter?

Mines running fine with V8 converter and V8 transmission controller, but I have bog stock msb101340 as I am happy with power/driveability around town where I do most of my driving, a tad less kickdown sensitivity on the open road would be nice though. And I love the early upshifts and 60km/h around town lockup.

So what TC/TCU combo causes the excess slippage that we should be aware of and do you tune for it?

And where the flock is your website with your services/fees?

It's not a remap but if anybody is interested it's possible to lock up any time if needed earlyer than the TCU does it by using a switch and a relay, here's the scheme, the wire which goes to the TCU's pin 32(output to lock-up solenoid) must be cut and there goes the relay's normaly closed contact, when the switch activates the (big blue)relay the lock up solenoid gets earth like when the TCU locks it up in normal operation... the red square on the right side can be another relay's coil or a resistor to emulate the lock up solenoid's resistance as the TCU to not consider it open circuit and go to limp mode... based on the statements of those who tried that(not me) it's working without probs.

D2 Autobox lock up.jpg

Originally Posted by sierrafery

It's not a remap but if anybody is interested it's possible to lock up any time if needed earlyer than the TCU does it by using a switch and a relay, here's the scheme, the wire which goes to the TCU's pin 32(output to lock-up solenoid) must be cut and there goes the relay's normaly closed contact, when the switch activates the (big blue)relay the lock up solenoid gets earth like when the TCU locks it up in normal operation... the red square on the right side can be another relay's coil or a resistor to emulate the lock up solenoid's resistance as the TCU to not consider it open circuit and go to limp mode... based on the statements of those who tried that(not me) it's working without probs.

D2 Autobox lock up.jpg

Some years ago I bought a transmission lockup kit from a major transmission organisation in Victoria.

When I finally got around to getting it fitted in my 4HP24, the local WA firm who rebuilt the transmission refused to fit the kit, saying it would quickly damage the box.
I was only planning to use it when doodling along in 70 kmph traffic, and never got an answer that explained his logic as he took off to serve a customer, and I haven't been back since (hoping the gurus on here would find a non damaging/long term solution).
I have a heavier torque converter out of a 4L Jaguar, but otherwise a standard 24 transmission.