Hi, I've had this problem on my P38 for a while now when it grinds while driving slowly (5-10km/h) in reverse. Got the car lifted at a workshop where they tried to listen to the source of the sound and found it coming from the torque converter. We're on a long roadtrip now and the grinding started happening when going slowly in Drive. Still have over 1000km left to drive. Any idea what could be causing this? Is it safe to keep driving, if it's only grinding while going slowly in D and R?
P38 1999 automatic transmission grinding
- Thread starter feyniriel
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Datatek
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If it's the torque convertor, I can only think of the lock up clutch, @Bemble is your man. The flex plate breaking up can produce noises.
What is lock up clutch? Would flex plate breaking noises start in a specific gear first before progressing to other gears? What would happen if you kept driving with a broken flex plate? We're in Southern Poland now, don't think any LR specialists are nearby..
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The lock up clutch locks the torque converter to improve fuel efficiency when cruising. I thought it only locked up at higher speeds but I may be wrong. I don't think a crack in the flex plate (aka drive plate) would be terminal, but as it is what connects the tourque converter to the engine (by lugs) if it actually broke it would certainly stop you from moving, and would make one hell of a noise. I'd have thought it were more dependent on engine speed rather than specific gear selection.... After all if it'd broken it'll be turning with the engine (or parts of it will).
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Datatek
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Is there any oil in the gearbox?
If the flex plate fails completely, you lose all drive.
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Datatek
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Torque convertor lock up occurs at 50mph in 4th gear and about 40mph if the box is held in 3rd gear.
We did an oil change a month ago, the old oil was almost black. It is full of oil now, we checked (tried to add more oil) multiple times and have seen no leaks. The grinding happens only at 5-10km/h, only when we are going very slowly in first gear either forwards or backwards. I will record a video in a bit after the transmission cools down a bit to show the grinding noise. It's not as bad as the one in the YT video.
Datatek
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Too much oil can cause problems, need to get the level correct. If the old oil was black, IMO the box is on it's way out.
Went outside after a few hours to take a video of how the grinding sounds like, but the car decided to stop making the noise. I noticed before that it seems to grind only when the transmission is hot, never when it's cold. Would that still indicate a flex plate problem?
We did drive for 9hrs almost continiously today, 400km through the mountains, so the car was under quite a bit of strain. Hopefully after a night's rest it will work normally tomorrow, I don't know what we'd do if we'd lose drive in Poland with a car laden with luggage and a small baby on board.. Are there any LR workshops between Rzeszow - Warsaw?
We did drive for 9hrs almost continiously today, 400km through the mountains, so the car was under quite a bit of strain. Hopefully after a night's rest it will work normally tomorrow, I don't know what we'd do if we'd lose drive in Poland with a car laden with luggage and a small baby on board.. Are there any LR workshops between Rzeszow - Warsaw?
Datatek
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Check that you have not over filled the gearbox. Transmission cold, engine idling, through all gear positions and back to P, oil should just trickle out of the filler hole, or if there is a dipstick it should be up to the full mark.
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Did they check the torque converter to flex plate bolts are all tight?
