Freelander 1 Td4 Auto hard gear change 3 to 4 - Nearly SOLVED

Using our low mileage TD4 for some long distances. This is the 27k vehicle bought a year ago. Now on 45k !

It had a cracked reverse piston which I replaced and all has been well. Fluid change and level check about 10k ago.
Now it has started giving very hard gear changes, only from 3 to 4 on an up change.

Quite a jolt from diff when it goes into 4th.
Any ideas ? Solenoid perhaps? Dirt stuck somewhere?

If anyone can clarify what operates on a 3rd to 4th upchange that would really help.

Thanks.

It'll be the 2-4 duty solenoid that has failed.

Failed or sticky ? One change in about 10 it is smooth !!
Thanks. Will resistance check before a change.

They fail, as the wires break where they are soldered to the connector pins.
I've repaired a couple over the years.

No fault codes showing. I can monitor the 2-4 duty solenoid. What am I looking for ? Getting 77% at idle and it drops when revved up.

So today it did the F4 + hill descent light on.
Stored fault codes are:
P0740- Torque Converter Clutch Circuit malfunction.
P0734 - Gear 4 incorrect ratio
P0735 - Gear 5 incorrect ratio

I'm thinking the second two fault codes are a consequence of the first?

Will be resistance checking all solenoids tomorrow.
Download of useful datasheet attached.

All solenoids and sensors test within spec.
Sprayed all contacts and found one round plug not absolutely 'clicked' shut.
Also, cleaned contacts on Jatco ecu.
Road test shows all now good, but time will tell !!

Yup, over an hour on country roads, no banging no fault codes!!

So how weird is this. Solved the problem for all of yesterday after cleaning and securing the round auto box plugs.
Today, much improved but a couple of bangs every 30 miles.

Can't see how cleaning contacts improves something but doesn't cure it??

Try doing it again? Could be broken wire that I disturbed ?

Any ideas. Bit miffed it didn't solve it completely.

Morning Andy, When I got my gearbox refurbed a part of the warranty was to get the radiator changed as they found that autoboxes were having problems if cooler problems. Some month my oil cooler was first leaking so got it changed. I had trouble
also with 2nd to 3rd and/or 3rd to 4th. Three leaks were found and fixed in the engine cooler and it improved. Had also bangings from one of the two once in a while and 2/4 duty was changed before refurbed, thinking of getting it changed completely now.

Hope that helps.

Thanks. Can you please clarify what solved the problem ? 2/4 duty chamge or oil cooler fix?

Did you get any fault codes ?

Thanks

You're welcome. the 2/4 no, oil cooler seemed to have improved, but since the cooler leaks it I can't remember to have heard.
Had no fault codes except the usual MAF ones for wires taken off.
Could scan the invoice to show you what I mean or they meant or maybe someone else has similar experience?

xxx

andyfreelandy said:

So how weird is this. Solved the problem for all of yesterday after cleaning and securing the round auto box plugs.
Today, much improved but a couple of bangs every 30 miles.

Can't see how cleaning contacts improves something but doesn't cure it??

Try doing it again? Could be broken wire that I disturbed ?

Any ideas. Bit miffed it didn't solve it completely.

Click to expand...

I also have error P0732 Did you solve this problem or has it not appeared since then?