I'll try to make this post as complete as possible. Feel free to use this post for future reference by clicking the "SAVE" tab in the upper right of this text box. This will save it into your personal Brickboard archive that you can look through as needed.

In your previous post you stated: "About a year ago we had to replace the radiator due to a leak in the tranny oil cooler."

Antifreeze contamination in transmission fluid is a death sentence for the tranny. The Ethylene Glycol in the antifreeze will eat the laminating materials (and the adhesive backings) in the transmission clutches for lunch. In an average automatic transmission, catastrophic failure typically occurs after about 3 weeks after the introduction of any sizeable amount of antifreeze. The fact that you made it a year is good testimony to the durability of these transmissions.

The only way to repair a transmission that has been contaminated by antifreeze is a COMPLETE rebuild. You will have to replace all the clutches, all the seals, and it would be a good idea to replace all the check balls with new ones while you have it apart. The torque converter will need to have a small hole drilled into it and the fluid completely drained out (and then the hole plugged with a small self-tapping screw). This is not a fun task unless you enjoy this sort of stuff. I would strongly advise to you consider acquiring a new/used transmission from a scrap yard rather than rebuilding your existing one.

Before you attempt to either rebuild or replace your transmission, buy yourself a copy of the Volvo 240 Transmission Service Manual (part number TP30868/2). This covers the BW55, AW55, AW70, and AW71 transmission that were installed in 240 vehicles from 1975 to 1993. You can order it online at www.volvotechinfo.com or your local Volvo dealership might be able to get it for you (click this link to go directly to 1990 240, then select "Service Manuals" and then "Power Transmission"). This manual covers specs, rebuilding info, tools needed, tranny chassis and valve body part numbers (and the revisions that were made), etc.

From time to time, Skip Albright has some of the Volvo Service Manuals for the AW70 transmission for sale in his ebay auctions. There's two there now (eBay auction numbers 2447500283 and 2209088684), but if you can afford the $30 or so from VolvoTechInfo, you will be guaranteed to have the latest printed revision. Some of the final revisions/changes may have been issued in Service Bulletins, rather than updating the Volvo tranny book.

Regarding your question about the ID tag. Yes, 03-70 is an AW-70 transmission. I'm in the process of pulling a 03-70L from an '89 740 to install in my '87 240. The addition of the "L" in the model number means that it is a lockup transmission, paired with a Lockup torque converter. At crusing speeds (not-accelerating and not below about 50 mph), the two haves of the torque converter will lock together (via an internal clutch within the Torque Converter) and thus give you the same gas mileage as a stick-shift (manual) transmission. This should result in about 2-5 mpg better than your current non-lockup automatic. If you have time to hunt through the scrap yards, look for a late '80s or early '90s 740/760 with an AW-70L or AW-71L. It should mate up to your 240 just fine. Note: the only difference between the 70 and the 71 is that the 71 is designed for 'Heavy-Duty' applications and is typically found in Volvos with Turbo-4 and V6 engines. Both the 70 & 71 transmissions will work in your 240. If you do find a Lockup tranny, be sure to get the torque converter too (mark the outside of it so you don't mix it up with a non-lockup torque converter). Here is a table (mostly correct) that covers the various applications and years of the various Volvo automatic transmisions (lockup/non-lockup, and heavy duty). Brickboard Tranny Table. Note, to the best of my knowledge the AW72 was only used on the 16 Valve B234 engines found in the 740 GLE from '89 to '92. I believe this is a lockup transmission, but uses an electronic solenoid to engage the lockup clutch (and requires a signal wire from the computer).

It would apear that the '92 and '93 240s came with Lockup, but if you end up pulling a 740 lockup transmission (like me), then here are some part numbers for the Volvo manuals. (should there be any internal differences between the 240 and 740 transmissions, these would be a good idea to have on hand):
TP31635/1 A-Trans. AW70/70L; AW71/71L; AW72L. Specifications, Disassembly, Measurements, Reassembly, Special Tools, 130 pages.
TP31642/1 A-Trans. AW70/70L; AW71/71L; AW72L (Design and Function, Fault Tracing, Repair and Maintenance. Specificaiton, Power Flow Diagrams, Fault Tracing, Remove Install Unit, In-Car Repairs, 112 pages.
TP30687/1 Power Train 700 series cars (Fault Tracing, Repair and Maintenance. Specifications, Fault Tracing, Clutch, Manual & Automatic, Drive Shaft, Axle, In Car Repairs Only, 138 pages.
Just about any of the above 3 books will guide you through a basic valve body removal and replacment, but the 32635 and 31642 books will have the most info on the rest of the transmission and repairs/rebuilding. The 30687 book covers most of the info you'll need, but also has info on the 700 series driveshafts, differential, manual transmissions, and a section on the ZF4HP22.

If your automatic transmission seems have an unusually fast engagement from 1st gear to 2nd gear, one or more of the check balls in the valve body is wearing down. It would be well worth your time to read the Brickboard FAQ on AW-70/71 transmissions. There's also a section that covers just the Hard Shifts. My '87 240 Wagon has about 240,000 miles on it, and it suffers from the hard 1-2 shift symptom. The newer AW-70L that I'll be installing does not yet have this problem, but I plan on changing the check balls in the valve body for good measure (preventative maintenance).

Lastly, if you're looking for some affordable transmission pan gaskets, your local Napa should be able to order them for about $2.50 under the part number of 17828 (it's not a regular shelf-stock item). They're good quality rubber gaskets (not cork or fiber/felt), but I'd strongly advise putting a bit of RTV on the pan bolts to keep them from backing out over time. Loose pan bolts are the number one cause of transmission leaks that I see on my friends’ vehicles. If you're looking for a new filter, a filter gasket (one), and a pan gasket, order the Napa kit 17816 for about $17. -but be advised, many of the AW70/71 transmissions use a spacer block between the filter and the valve body so you will actually need two filter gaskets. Unfortunately, Napa does not sell the filter gaskets by themselves, but any Volvo dealership has them for about $4 with a Volvo part number: 3520329.

For more info on pan cleaning procedures, check out the following Brickboard posts:
http://www.brickboard.com/RWD/?id=645312
http://www.brickboard.com/RWD/index.htm?id=655545&show_all=1

Proper procedures on checking your transmission fluid level:
http://www.brickboard.com/FAQ/700-900/TransmissionAuto.htm#TransmissionService
http://www.brickboard.com/RWD/index.htm?id=717912

Proper procedures on flushing your transmission fluid:
http://www.brickboard.com/FAQ/700-900/TransmissionAuto.htm#7XX940FluidFlush

God bless,
Fitz Fitzgerald.

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'87 Blue 245, NA 229K