Originally Posted by SubtleIceCream
Hello Doctor, it has been a while. I don't suppose you have that manual?
Also this: MPV Club
"2002 MPV ES with 68k miles
I resolved my transmission issue and am posting for others who may have a similar issue.
RE: Mazda6/MPV interchangeability of the FWD
5spd transmission (JA5A-EL / JF506E ).
- Mazda assigns a different part numbers to each although they share many of the same internal parts
- I could never determine the exact differences but since the Mazda6 version is $2k cheaper from the dealer I don't expect they are a direct swap
My problem was that when the trans shifted into 3rd gear it slipped and you couldn't accelerate enough to test 4th or 5th.
1st, 2nd and Reverse all seemed to work fine. If you drove in '2' it was fine but of course you can only go 40 mph
tops. Fluid was a bit burnt.
I removed the driver's front wheel and upper/lower trans mount bolt so the transmission end cover could be removed and the High/Reverse drum extracted.
I found my reverse clutch and steels were completely burned but high clutches looked fine (High clutch operates 3rd, 4th and 5th gears). I dissasembled further and the other clutch packs all looked great.
VERY careful inspection showed the high piston had a hairline crack that allowed the fluid to drain from the high piston that rides inside it. This allowed the reverse piston to partially engage the reverse clutch pack when it shifted into 3rd (or 4th/5th) and burned it up.
I found cracks in the reverse/high pistons are very
common in these transmissions (check the same trans used in Jags) so I replaced both pistons (with updated versions) + seals and reverse clutches/steels, reassembled and all now works great.
Cost was $120 in parts + $33 in fluid to flush the entire system.
Note: You are able to disassemble the majority of the internal components through the end cover + remove the valve body via the front cover WITHOUT removing the transmission from the car. It is detailed work but far cheaper than paying the dealer $3500 + install cost for a complete replacement I didn't need."