BenzWorld Junior Member
Date registered: Jul 2014
Vehicle: 2008 ML320 CDI
Location: United States
Mentioned: 0 Post(s)
Quoted: 3 Post(s)
Transmission repair or replacement
First of all, I'm pretty sure I killed my transmission. It's a 2008 ML320 with about 175K miles on it.
Over the course of trying to get rid of drivetrain noise, I have replaced the front wheel bearings, rebuilt the front differential, and, recently rebuilt the transfer case.
While removing the transfer case, I removed the girdle that supports the tail of the transmission, and I was stupid enough to support the transmission with a decent sized board on a jack under the oil pan. I was concerned that this seemed to be dent the pan, but after everything was back together it looked OK, so didn't do anything more about it.
A few weeks and a few hundred miles later, the transmission started shifting badly and slipping. Pretty sure what happened was that the deformation of the pan blocked proper oil flow and damaged the transmission.
I took it to the shop that does my regular service work, and they installed a new pan and serviced the tranny. That helped things. Got rid of the hard shift when coming to a stop, but the slipping in first and second came back pretty quickly as soon as things were warmed up. They reported that the old fluid was quite burnt.
At this point, I'm thinking I either need a new transmission, to repair this one, or to replace it with a used one.
I really like my car, but I don't have much budget for stuff like this.
The shop came back with $5300 for a new transmission.
Looks like I can get a (theoretically good) used one for about $1100 including shipping. From what I've learned, I would then need to send out the TCM to be revirginized or made VIN agnostic so it could be used in my car.
I've never rebuilt a transmission before, but I've rebuilt engines, steering racks, the aforementioned transfer case... I wouldn't mind taking a stab at rebuilding the transmission, but I'm wondering how likely that is to be successful. How likely is it that the restriction from the pan caused damage that's reasonably repairable, like needing new frictions? Maybe steels? Bands? Looks like OE part rebuild kits start around $500.
Neither CEL nor ECU codes have shown up for this. As far as the control modules are concerned, everything's fine. So, no sticking solenoids as far as can be told.
What about getting a used one and switching my TCM into it? Is the TCM married to the valve body as well as the ECU, or just to the ECU? How much is involved in swapping the TCM and/or valve body?
Thanks for any ideas and help!