P38A Auto box issue

Hi I'm pete own a 1999 p38.2.5 auto love the car but she when it gets hot it get really sluggish to the point why I can have my foot flat to the floor and it will take a good 2-3 mins to move In reverse but when it's cold it's fine I guessing it need a gearbox service, but it also has a slight chatting noise when cold in reverse and drive only but more noticeable (louader) when hot I have removed the inspection cover underneath and saw the previous own had welded the flex plate my my concer is the start ring as wear marks on it from the bell housing could this be lose bolts and allowing movement and letting t/c slip any ideas would be greatly appreciated thanks

Welcome.
Is there any oil in the box? That would be my first check.
You check the level with the engine cold and idling, remove the filler plug and oil should trickle out.

Yeah cheeked all that is going for a service soon but that wont explain the starter ring rubbing as you can hear it chatting when its turning over

P38parris said:

Yeah cheeked all that is going for a service soon but that wont explain the starter ring rubbing as you can hear it chatting when its turning over

Click to expand...

It's difficult to see how the starter ring could rub on the bell housing, it's on the periphery of a cast steel lump that is bolted to the crankshaft. The flex plate is bolted to this lump. I take it the starter is disengaging?

Yeah starter is disengaging it dose it more when it's hot it stops chattering when you put you foot down only on idle it will chatter when you select reverse or drive

P38parris said:

Yeah starter is disengaging it dose it more when it's hot it stops chattering when you put you foot down only on idle it will chatter when you select reverse or drive

Click to expand...

That does sound like the flex plate is cracking up or possibly loose.

Flexplat has been welded up by previous owner as you can see where they ground the weld of but surely wouldn't explain the go slow when it's hot

P38parris said:

Flexplat has been welded up by previous owner as you can see where they ground the weld of but surely wouldn't explain the go slow when it's hot

Click to expand...

Where's it welded? If it's to the torque converter then the plate could be loose/ cracked where it bolts to the crank, photos may help.

Its welded by one of the 3 bolts I'll get a photo and video tomorrow

P38parris said:

Flexplat has been welded up by previous owner as you can see where they ground the weld of but surely wouldn't explain the go slow when it's hot

Click to expand...

You would think not. But if the flex plate is adrift, it could perhaps have damaged the oil pump drive from the torque converter to the box.
Bemble or James Martin would know more.

Datatek said:

You would think not. But if the flex plate is adrift, it could perhaps have damaged the oil pump drive from the torque converter to the box.

Click to expand...

.

Welding a flexplate isn't a good idea, and tbh who is that cheap?

More to the point who drops a gearbox and decided to half ass a repair!!

SMH..

Also worth noting, flexplates are balanced.

Right I done hour round trip today and about 20 miles from home it became sluggish and lazy at changing gear when I got home I could hear a thudding noise from the gearbox as I layed underneath it is a bit concerning now any I dears

Keep your RAC card in the glovebox.

P38parris said:

Yeah cheeked all that is going for a service soon but that wont explain the starter ring rubbing as you can hear it chatting when its turning over

Click to expand...

Has anyone put the starter from a v8 onto it? It won't fit a manual but it will fit an auto but it protrudes more so might well catch. Diesel should be a Bosch unit.

@jamesmartin is the gearbox guru. I'd have though change the oil in the first instance, maybe with some Lucas Transmission Fix and see if that helps.

Thumping underneath sounds like UJs so you need to check those thoroughly.

Slow when hot: no loss of engine power? Definitely gearbox related?

Sounds like it could be a UJ.

Wouldn’t hear a UJ laying underneath not driving

No its not a Uj think the torque converter is eating its self