1997 P38 Automatic torque converter lockup.

[rockyrangie]

hi can i seek some advice, my Auto changes fine BUT seems to change really early in all gears from 1st to 2nd almost instant, at 10km, 2nd to 3rd 25km, 3rd to 4th at 45km, then tourqe lock up at 60km in 4th all changes are smooth and not cluncks ect but even under some power it changes really early, and if you start going up hills it just labours and does not change back gears or unlock the tourqe converter, i seem to drive around manually changing from (D) to 3rd on the shifter.

AS well the tourqe lockup in 3rd is at 50km as well , i know all the oils were changed lately and they could be a bit overfull so will this cause it .

and in town driving should it be left in 3rd and then use 4th (D) for highway or ( D) all the time.
all coments greatly appreciated.

[Keithy P38]

Mine's much the same, I believe it's normal in economy mode, different if your in sport mode. Mine held 4th locked through the Rex range the other week, pulled the big girl at 1000rpm up no worries, however an earlier gear would have been better.

[benji]

Mmm, mine seems to be a bit different. 1st-2nd won't happen at anything under 1800rpm, even on really light throttle. 2nd-3rd the same revs, and 3rd-4th simply won't under 2000rpm, even if I hold it at 1900 with barely no throttle. I'd like it to change at roughly 1500-1600.

I know the EAT ecu has different learning modes etc, so maybe I need to disconnect the battery overnight, and drive it more gently. Mine will unlock the torque converter at 1200rpm in 4th.

Just wondering though, under a heavy throttle, it's lock the convertor in 3rd, then change into 4th with it lock for half a second before it unlocks, and then will lock it again at the right time. Has anyone else found this?

[ytt105]

I'd like a switch to be able to lock and unlock at will.

A half gear down when towing up a rise would be great!

Anyone now if that is possible?

[benji]

Mmm, I like that idea. A few years ago we took a Delica to Perth and back, 8 people, and a full trailer. The lock-up button was great!

pin 42 of the eat ecu supplies the signal to lock up the torque convertor, what type of signal it is though....12V, 5V, PWM?

I wonder if the ecu will log a fault over this though.

[Blknight.aus]

1997? should still be a hydraulic brain box if my memory serves.


check the operation of your kickdown/throttle pressure cable.

[Scouse]

1997? should still be a hydraulic brain box if my memory serves.


Range Rover, not Discovery.

[Blknight.aus]

ahh

burn it, buy one in manual with the insurance money.

[Scouse]

They weren't available here in manual form.

[Keithy P38]

Seen the 4wd action article yet? Duramax with Allison 6speed auto would go down nicely!

[Blknight.aus]

They weren't available here in manual form.

well thats just gayer than fruit loops.

ok, so with a little more seriousness...

plug a diagnostics unit in and see what the MAF, MAP and TPS are doing.

(combined with some ECU derived data they give the same info as the kickdown/throttle pressure cable to the autos brain)

[wanglemoose]

P38s tend to go up the gears early, some one at the mental institution who wrote the original programing of theses things seemed to think that high gears low revs (regardless of engine labor) was better for economy. mine also changes early like yours but when i hold mine on the floor in sport mode mine also runs off the end of the tacho b4 it changes, 6250ish according to the hawkeye. the best thing to do if you want to change the way your auto changes is to get a programmable auto ecu and use a manual becm.

[benji]

or you could just let it run low on oil..... I wondered why mine would barely change below 2000, until I checked the level.....

couldn't it just be driven around with the sports mode on?