From the site below...
"#816. We recently received a question regarding the maintenance schedule and fluid requirement for the U.S. manual T-350 transmission. It seemed like a pretty straightforward question, however while checking the 2001 -2003 service and owners manuals' we discovered a good deal of contradictory information. My thanks to Chuck Schneider for bringing this issue to our attention. I recently contacted DC for clarification and they replied:
Thank you for your email to DaimlerChrysler regarding the Chrysler PT Cruiser. The transmission fluid and maintenance schedules are the same for all model years of the PT Cruiser. For the manual transmission, severe usage requires transmission service every 48,000 miles - please refer to Maintenance Schedule B in the owner's manuals. The recommended manual transmission fluid is Mopar Manual (Type MS-9417) Transaxle Fluid." http://www.ptdoityourself.net/tl/tl_33.html#816
Although not called for in the manual, personally I'd use Chrysler's "severe usage" spec as a good rule of thumb, and change it out each 50K miles regardless of service intensity. Check the transaxle housing -- evidently it may indicate the proper lube. Any name brand which meets that spec (and is of the proper weight) will do.
Quotes from other webites:
-Capacity is apparently 2.1-2.8 qts.
-The 2004 manual tranny apparently uses ATF+4 instead..??
-Mopar recommends using their Type MS-9417, but does mention gear lubricant meeting API GL-5 and SAE 75w-90.
-There's a sticker under the transaxle housing (near the drain plug) that indicates Mopar Manual Transaxle Lubricant Type MS 9417 be used. http://ptenthusiasts.org/forum/showthread.php?t=13883