1998 S500L gear box went BANG?

[Borys]

I'm devastated. Recently done a big service on my merc icluding gear box oil and filter change. Today at petrol station, once shifting to P I heard a BANG. Well filled her up started and noticed that on P and N a got a bit of a noise. Put in to D and it gone quiet. Driven home with no probs. Later wanted to drop my miss to work and in half way starting from traffic lights heard a BANG again and the noise was with me once driving, over 30mph goes quiet again. Car shifts thru gears no probs. Stopped and on P and N horrible noises are coming from the gear box.
Anybody first thoughts?

 

[brucemillar]

Are you 100% sure your newly fitted filter has not dropped off?

 

[Gaz74]

Torque converter dying? From your description the gearbox seems ok most of the time. If it was completely f**ked then surely the noises would be constant?

Hopefully someone more knowledgable will add more to this theory

 

[Borys]

Will take it for investigation on Tuesday to my m8 garage his got a ramp.
I'm just depressed as I always take care of my cars - bad luck I recon. This is my merc no 6 and had probs with gear box before.
I really appriciate any input from you guys which could direct me so I don't have to go to the mechanics and pay a fortune to get it done. Most of things can do myself.
Thanx

 

[Gaz74]

That's the problem with most cars, transmissions aren't generally something you can tinker with on the driveway! But, if you have a pal that can have a nose around, then make the most of it. I'm still not convinced it's the actual autobox, purely because you say it's ok then it's not. In my mind, if something is fu**ed, it stays fu**ed!

Good luck fella, let us know how you get on

 

[Borys]

Just had this reply on other forum, sounds reasonable cause :
- "Yes I had this on 99 ML430. Same 722.6xx transmission. The early 722.6 had problem with bushing between two shafts. This bushing wears out and tranny needle roller bearings and torrington bearings aren't getting enough lubrication due to oil pressure loss through that worn bushing. The bang you've heard was a roller getting through the teeth of the gears. Drop the pan and check for metal shavings".
Time to get dirty

 

[Gaz74]

Certainly sounds plausible, I think that if your pal can drop the transmission out and either inspect it himself or pass it on to a decent specialist to determine if that is the cause, it could be a relatively straightforward fix. Fingers crossed for you mate.

 

[Borys]

Ok
Had it inspected.Tourqe converter cracked and smashed the box.Car doesn't drive any more.Got my new box in today for 400 quid.Now just need to wait for a slot at the garage to have it fitted.Was quoted 180 to do so.
Hope fully my baby will be back soon with me

 

[trapperjohn]

Hope the garage can fit you in soon. Happy miles when you get it back.