i bought an '86 740 wagon, d24t with a bad 4hp22 and now i came across an '83 240gl, d24 with a good bw55; is a direct swap of the 4hp22 to the bw55 possible/good idea?

thanks
mike

Making the swap happen on a Gas engine can be done. Do you know if the swap can be done on the Diesel engine as it appears that is the car that Emdog needs to put the transmission into. The bellhousing is diffferent fron Gas to Diesel and also the nipple on the end of the torque converter that goes into the crank. The bolt patten on the torque converter and flywheel are different.

Are you sure that the '83 240 has a BW55? I was under the impression that the last years of the BW55 were '80 and '81, and all the '81+ 240 Turbos and the '82+ 240 non-turbos received the AW-70 transmissions. To confirm, if the transmission ID Tag says 03-70, then it is indeed a newer AW-70 transmission (also identified by the overdrive button on the shifter lever).

Regarding the conversion, the two primary parts that you will need are the new AW-70 unit, and a driveshaft of the correct length with the correct center bearing (other parts are required, as mentioned below, but these are the most significant). The new transmission can be either an AW-70, an AW-70L, or the AW-71 (equipped to turbo vehicles) and can be found in just about any 200/700 series car that had an AW-7x in it (most of them), but the '89-'93 740/940 vehicles are almost certain to have the improved AW-70L (with the Lockup Torque Converter). Some AW-70L units were fitted to select 740 Wagons starting in '87, but you'd be better off shopping the '89+ 740 sedans and wagons.

You'll need to pull the driveshaft from a 740 unit that was originally equipped with an AW-70, or any 760 that had the B230FT (4-cylinder) engine but did NOT have Independent Rear Suspension (IRS was used on '88 and later sedans but not the wagons). This driveshaft will be the appropriate length and have the proper bearing and support system to fit your car. Be advised, the 240 driveshaft would require modification, while the 740 or 760-Turbo driveshaft will be a plug-and-play operation.

The entire procedure for converting a ZF4HP22 to an AW-70 or AW-71 is outlined in the following section of the Brickboard FAQ. I thought it would be worth mentioning the above information for clarity.
http://www.brickboard.com/FAQ/700-900/TransmissionAutoConversionZF-AW.htm

God bless,
Fitz Fitzgerald.

--
'87 Blue 240 Wagon, 255k miles.
'88 Black 780, PRV-6, 147k miles.

positive on the bw55(id tag) and knowing car manufacturers, they use what they have left over and don't write the 'facts' until afterward so to find something that isn't 'supposed' to be there isn't that surprising.

and as skafasis said, the bell housing bolt patterns are different from diesel to gas and that's why i considered the 55 at all; it's from a diesel.

The BW55 is 3-speed, no OD; probably not a good idea.