Thread: Question re D2 ECU for auto V8 - or TD5?

I think its the auto transmission computer you might be after. This was on FB recently in the Modified LandRovers Australia group.

Error

Elward Would

August 22 at 9:31 AM

Hi guys, I've just swapped over my td5 automatic gearbox controller to a v8 auto controller, and what a difference!! Not reving her head off,smoothed out the Td5 vibrations locks up @60kms instead of 80-85, td5 is tuned similar torque to a v8


Clint Blay have you remapped your TD5. What size tyres are you running?


Elward Would 245 70 16


Clint Blay Elward Would ok cheers. I thinkiwillhaveto get myass in gear and try this. Can you get to it without removing the seat?


Elward Would Clint Blay ya 3 10mm nuts once you remove the seat surround and 1 Philips screw that holds the clamp, after the swap reset then go for a drive so the computers can talk to each other and start to relearn, is yours tuned?


Clint Blay yeh I have a td5 inside stage 1 remap. I'm running 265/75s but I have re-geared my TC back to defender ratios. so close to stock gearing. Pulling the seat was what had been putting me off trying it. not that it is a big issue to remove it. but we have a couple of the v8 controllers. so will give it a go.


Clint Blay I'd heard rumors about it being a good mod, but not actually spoken to anyone that had done it. So thanks for posting about it.


Simon Lun Just unplugged the TD5 controller and plugged in a standard V8 controller?


Elward Would Yip


Justin Codr Thats good to hear, keen to try this thanks!


Benji Harrold Paul Harrold - i do believe I've got the same tran ecu as he's put in in the white p38....


Harry Hiemstra Does it have to be a disco one or will a p38 4.6 one work?


Tasman Binder Would this be a hack for making the diesel work?


Harry Hiemstra Nah, for Justin's td5...


Elward Would Discovery works get one close to your vehicles year of manufacture, mine was a 4litr controller,rather then the 4.6 as the tuned td5 matched closely the torque out put of the 4 litre v8


Justin Codr My guess would be d2 only but worth a try

Not sure why it would help a td5 with big tyres??
as far as I know the V8 locks up earlier in 4th, when warm, around 60 kays,
I'm not sure at all about earlier lockup speeds,,
A V8 torque converter would help a td5 with big tyres...

Originally Posted by Pedro_The_Swift

Not sure why it would help a td5 with big tyres??
as far as I know the V8 locks up earlier in 4th, when warm, around 60 kays,
I'm not sure at all about earlier lockup speeds,,
A V8 torque converter would help a td5 with big tyres...

Can help with big tyres because the standard TD5 trans ECU ensures no 4th lockup until 80 kmph, which gets closer to 90 with oversize tyres like my 265 75 16R. So, if I can swap over the ECU and get V8 style lockup at lower revs (particularly when driving sedately), then 70 -90 kmph cruising becomes lower revs/more comfortable, and if a light foot, hopefully slightly better economy?

I have a HD (V8 style) torque converter, but that doesn't help this situation because the trans ECU is boss man for control of gear change/lockup speeds.
Hope this helps.

PS it looks like the oft repeated comment that TD5 auto lockup in 4th was set in stone in the electronics at the factory and not able to be modified (except possibly with using compushift?) is found to be a furphy

Hmmm ...
I'll have to give it a go on brother's TD5.
I have a V8 spares with many bits still on it.

Will try to find the time to remove the trans ECU and fit to brother's TD5.
His has a TRS modded ECU, and seems to rev it's head off wastefully too.

He recently had the torque converter rebuilt and it has helped a little, now just to get the box to shift and lockup earlier too.

as I see it---
LR devised the higher lockup as a sort-of cvt, once the correct revs are reached the auto slips until the correct speed is obtained.
funnily enough the old 4L used to lockup then road speed and gear speed increased together, but the 4.6 operates like a TD5, but for a different reason


Why not the Compushift , GW?

Originally Posted by Pedro_The_Swift

as I see it---
LR devised the higher lockup as a sort-of cvt, once the correct revs are reached the auto slips until the correct speed is obtained.
funnily enough the old 4L used to lockup then road speed and gear speed increased together, but the 4.6 operates like a TD5, but for a different reason


Why not the Compushift , GW?

As I understand, the compushift is quite expensive, and I'd like to use that dosh for other goodies.

I understand the LR rationale for the higher speeds/revs lockups in the TD5 for better performance matching etc, but if you drive like a nanny as I often do, I'd be interested to see if I can improve my fuel economy and reduce the revs noise with light pedal/lower revs/quicker entry into 4th lockup as I quietly tootle around - usually in the 70 kmph region.

Originally Posted by Pedro_The_Swift

as I see it---
LR devised the higher lockup as a sort-of cvt, once the correct revs are reached the auto slips until the correct speed is obtained.

Really good observation Pedro, it really does act like a CVT and that's how I drove the car initially.
Now I try and drive so it gets locked as quickly as possible and stays locked in both 3rd and 4th

Originally Posted by gavinwibrow

and reduce the revs noise with light pedal/lower revs/quicker entry into 4th lockup as I quietly tootle around - usually in the 70 kmph region.

Try running it in third lockup at those speeds and see what you think.