5r55s Suggestion

wiseguy83

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Hello, New here and haven't browsed message boards since I sold my 87 Thunderbird about 15 years ago (almost did the HO swap, timing chain grenaded, and then I bought the Mustang.)

I've got a 07 Mustang GT with getting close to 190k on it, had it since new.
Recently, and unsurprisingly, it's having trouble shifting into reverse until warmed up and is slipping gears, bucking, and doing a few other strange things. I don't believe there is a leak or I would have seen something. It's original and unfortunately had only ever been serviced once.

I've finally allocated some funds to start doing long overdue repairs and upgrades just in time as the transmission seems like it's on its last leg.

Please forgive me if this has been discussed to death but I did a fair amount of searching...I'd like to either rebuild or buy one beefed up a little bit as I work through restoring and upgrading parts.

I've read here in a few threads that rebuild kits don't fully address all of the issues (something about sleeves to prevent fluid from slipping by?) Also, read here to just buy a used one with fewer miles and burn that one up as apparently, these go out all the time. I've got a budget of about 3-4k I'm working with. Is there a decently built (affordable) aftermarket transmission I can grab, or if I go rebuild what do I need to look out for?

Thanks in advance.
 

stkjock

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WG - there's never been a great solution for built 5r55s as I recall.
5-Speed or Automatic? V6 or V6?
dude, the title indicated what the trans is and the text tells you its a GT -
 

JC SSP

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Appears prices range from $2k-5k+ depending from stock, mild to wild… TCI makes one and they are an established company but I am sure a Google search will provide several other options.

I have 120k on my 05’ GT and so far no tranny issues, but already prepared for that day… I have a family owned transmission shop that has done several autos for me so I would do a good HD rebuild with a performance converter. Estimated is $2-3k.
 

DieHarder

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Check this out: https://www.aj1esuperiorsolutions.com/ford-servo-bore-fix.html

I have the same kit but haven't experienced major issues to date so I haven't replaced them yet. The only issue I have is a tendency once in a while not to want to go into reverse; everything else operates normally). It's still a job so likely to run several hundred or more depending on who does the work but results have supposedly been good and doesn't require a full rebuild (of course assuming the bores are the problem and no other issues).
 
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DieHarder

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Check this out: https://www.aj1esuperiorsolutions.com/ford-servo-bore-fix.html

I have the same kit but haven't experienced major issues to date so I haven't replaced them yet. The only issue I have is a tendency once in a while not to want to go into reverse; everything else operates normally). It's still a job so likely to run several hundred or more depending on who does the work but results have supposedly been good and doesn't require a full rebuild (of course assuming the bores are the problem and no other issues).

Another vid on the bore issue:
 

07 Boss

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Unfortunately these trannies can only be built up so far. I'm on my third. The first was a stock one and then I went with Level 10 "Bulletproof" unit. Abused the shit out of that and then went with a local guy to rebuild it and this one has been doing decently well but I hardly race anymore. Tuning may help a bit by upping line pressure but it will make the ride a little more harsh. But yes servo bores are a big thing along with the actual bands. I would go with colene steel bands like the alto reds. New solenoid pack and pump would probably be in order too. This might be a time to look at a convertor also if you wanna go that route.
 

JC SSP

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This might be another one of those "Houdini questions" OP posted and disappeared... LOL
 

eighty6gt

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Probably traded the car for a 5.0/6speed auto with a circle d and is loving life
 

JC SSP

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Yeah not too many kids can bang a stick anymore. Lol
 

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