Need quick V70/C70 transmission swap advice

[elc32955]

OK, it looks like my M56 tranny in my 2004 V70 T5 is hosed beyond local repair capabilities. Forward drive gears are fine, however going into reverse the car may hop out of gear and the gears will grind unless the shifter is held into reverse with backpressure on the gear lever while the gear is engaged and the car is moving backwards. My indy has looked at it and recommends a tranny swap. Best locally I can do a new tranny for is around $2,800.

Here is the rub. My M56 is part 8252112, there is another M56 available (used, warrantied salvage yard tranny with 60K miles) from a 2004 C70 with part number 36050431 that I can purchase for a swap. The question here is are the ratios the same between the two trannys, and if not what will this do to the car computer, will it throw a CEL or do other things? The fitment between the two transmissions should be identical, but neither me or my indy has done enough modding on Volvo to know all the permutations. I've seen the chart with the ratios between the various transmissions, but I'm not sure which tranny is in which car.

Can anyone shed some light on what might happen to my V70 if we do the swap?

Thanks
Eric

[elc32955]

OK, more information. The current transmission in my car is a M56LK (2004 V70 T5) with p/n 9482209, the proposed swap tranny is a M56HK from a 2004 C70 with p/n 9482122. Other then the differences between the final drive ratio and the different ratios between 1st and 2nd gear, are there any major show stoppers here? I've seen talk of differences in slave cylinders (internal vs. external) and would hate to find out that after paying for a tranny and sending it halfway across the country that there was a difference there.

Thanks
Eric

[JRL]

I'm guessing it's just the gear ratios but don't shoot me if I'm wrong
(ALL have internal slaves past 1999)
Flywheel match up could possibly be different, you're putting a tranny from a 2.4T into a 2.5T car, this IS a different engine

[elc32955]

Pretty much the same motor. The 04 C70 donor car is a high pressure turbo version (2.3), same as my T5 (2.3). I'm really hoping this is a bolt-n-go type application, but even the Hollander database at the parts vendor didn't list a V70 interchange. I'm stumped.

[chrism]

"...going into reverse the car may hop out of gear and the gears will grind unless the shifter is held into reverse with backpressure on the gear lever..."

That kinda makes me wonder if there isn't an issue somewhere in the shifter or cable or arm or ???

Have you carefully looked it over to see if something might have just gotten a bit tweaked out of whack? Or maybe something in the shifter itself coming loose?

How about shifting it into reverse, then disconnecting the cable at the trans end and see if the lever tries to center itself in a detent slightly off from where the cable put it.

I don't mean to sound as though I'm doubting your diagnosis, but I would want to make sure I've totally exhausted all other possibilities before I undertake a trans swap.

[elc32955]

Understand, and very good thought. We did go through the procedure of disconnecting the shifter early on to check, it was still acting up with the same symptoms. It's definitely a problem inside the tranny. It's almost like the unit is bent internally somehow, as long as backpressure is held in reverse it doesn't pop out of gear and runs fine in reverse. Let the lever go and it will probably hop out of gear in one or two seconds after you start to let the clutch out and GRIND.....

So I'm down to figuring out exactly what the difference is between the 2004 M56LK (currently installed) and the 2004 M56HK transmission versions. If it's just ratios it's not a big difference. Both units have the same final drive ratio from the labels on the transmissions, the yard sent me a pic of the label on the HK unit that came out of the C70.