Gearbox query

Hi all. Hope everyone is well in this current time.

I have a 05 l322 td6 range.

Iv been having issues with the gear box. If I'm going up a steep hill (Manny where I live) car doesn't want to change down to power up the hill. Then wen it does drop down. Dropped down 2 gears and revs hit the roof and transfail warning flashes up. So pull over stop and start the car and it drive's fine. Iv had the gearbox flushed through and it's happend again. Should I just pop it into manual and pick the gear myself or is it somthing more sinister. Would adding a additive help or is it not worth the hassle as I don't have a ramp.

Thanks form any help Grant.

The GM5l40E is renown in RR circles for being made of melted cheese.

The valvebody solenoids are usually the weak link, as they wear they cause the lock up clutch and the drive clutches to slip which fills the solenoids with shyte, which then causes even more issues, by this point the gearbox is scrap..

It is rare for the 5L40 to give electrical faults, it is almost always a mechnical one.

Hi thanks
Is it somthing I could sort or is it a garage job.

Depending on how brave you are you can do it yourself but you will need a new valve block by sonex I think there called
A couple on here have done a full rebuild with advice and support from Bemble on here, have a look for some of his threads.

Ok. Will do thanks

Been a long time difference but the box finally died. Took it to the garage and it was ithe clutch pressure plate in the gearbox that died.

Grimlock1234 said:

Been a long time difference but the box finally died. Took it to the garage and it was ithe clutch pressure plate in the gearbox that died.

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Thats due to the naff valve body loosing pressure as they wear, as mentioned above Sonnax valve body required or it will need doing again

Yer. Had the hole thing rebuild. Next stop injector lol

Grimlock1234 said:

Yer. Had the hole thing rebuild. Next stop injector lol

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But was it done with the modified valve block.

Iv. Checked and yes it was.

Grimlock1234 said:

Iv. Checked and yes it was.

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That good i would hate to see you go through it all again some time down the line