Technical So, just how hard is it to rebuild an automatic transmission?

My suggestion get a ATSG manual read it then decide.

 

Just that cover picture of all them goofy parts that make no sense tells me one thing...NOPE..don't even think about it

 

Went out a while ago and looked, can't drop the pan with it in the car, wishbone is right in the way. I don't think the spring will flex enough to lower the bone enough to get the pan to clear the filter. Looks like it's coming out anyway.

 

You said you had the pan off and it got water in it . My son was 4 wheeling with his blazer and got water in the transmission through the vent. It smoked the clutches in no time.
Also you could be sucking air if you didn't get the filter on right. that will cause your trans not to work.

 

I had the pan off before I put it in, changed the filter and gasket then. It has reverse, just no forward. The idea of a stock valve sounds feasible, but it’s still gotta come out to find out.

 

Clean all your parts in a tub of solvent at home, but bring the main case and extension housing to a shop with a jet washer to clean, that will save a lot of time and do better at getting small debris out of crevices.

Measure endplays etc. before dismantling as you may have to replace selective fit bushings to correct them.

A drill press with quill lock is a great tool for compressing springs and clutch packs.

When adjusting the TV cable, check pressures as well as lengths.

 

From experience there is almost always a guy around who does transmission work in a dealership or shop in the day time and then does a side job or two a week in the evenings for extra cash. Most of the ones that I have had work on stuff do bench jobs fairly reasonably asking about what their share of flatrate for a bench job would be in the shop. Personally I'd rather take on a side job to make the cash to pay for having a transmission done than do one myself. I've done them but don't like doing them.

 

$900 is not terrible to me. I've done Powerglides (lots of "front" jobs), Ford-O-Matics, a few C4s, Turbo 400 and helped a few guys with theirs. They are messy and take up a lot of space when you gut them. Any time I needed a press I'd take the item into work and use the press.

 

If you get the car high enough in the air, the wishbone will move a long way.
Especially if you loosen up on the spring u bolts at the x member.

 

I look at it this way, with all of the other things i know how to do, the money I save on those tasks are put toward the tasks i don't know how to do, i.e. upholstery and transmission work lol. When i price paint work, people often look at me like my head is on fire. Then they do it themselves. What's the worst that can happen? Car looks bad? I'd pay a guy that knows what he's doing.

 

Pay the $900! You will be a lot happier in the end. My brother watched videos and did his own transmission. He had that damn thing in and out of there 3 times before he got it right. All that labor, Fluid and headaches would have been worth $2000.00 to me. Goodluck

 

Yup, and that will likely come with a warranty, too!

I can rebuild automatics, but still pay others to do them for me, except when it is one that I cannot find a shop willing to touch.

I am elbows deep in a TH425, which is 95% a TH400, with the remaining 5% being just nuts-and-bolts stuff. Still, some shops appear to regard them as "impossible to work on". For those that don't know, these are like a TH400, but with a transfer case chain between the pump, and the rest of the transmission. They were found in Toronados and Eldorados, with big engines.

I recently did a TH350 for a buddy of mine, including all new bushings, and a few upgrade parts, while he waited, in 2-1/2 hours, on a Saturday. He's dollar down, and his work truck dropped dead. He was back up-and-running by Monday.

 

Gimpy,

I was gonna ask what a 425 is,,thanks for the info .
I bet they are kind of hard to get done,,,considering how many Toronados and Eldorados there were with big engines ?
I bet a lot don’t know how to do anything to them other than service the fluid ?

I’m glad to see you helped your friend out as well,,,,that is a lot of work for not wanting to touch them .
Good man !

Tommy

 

It's kinda weird how nobody seems to want to touch them, and those that do want enormous sums to do so. I am not talking working from the point of one being in a car, either, just out loose. There really are not any unusual parts in there. The only thing found in them that is not found in regular RWD transmission is the chain and sprockets, and those don't require service, just replacement, when trashed (and they usually are not).

TH350s are probably the easiest of the lot. Lots of parts, but not a lot going on.

 

I have done several Mopar autos,,,and Asian too .
After the first auto,,,,it’s not too bad,,,just makes you stink like crazy from the fluid .
Really not that hard at all .

I can see the guys wanting premium money for the 425 s though,,,most of those cars were owned by people that usually could afford it .
Like you said,,,not that much more involved though .

Tommy

 

Draining the oil out of these critters has been a problem since the manufacturers found that they could save 31 cents per vehicle by omitting the plug. So then your left with oil running off your elbows and you gotta replace the gasket. Next time you get the pan off install a drain plug. Drill a 1/2 inch hole in the location of your choice and use a 1/2 20 plug with this modified nut welded, brazed or soldered inside the pan. Take the nylon washer off and snug up the plug before welding. The oil change will, now, be a pleasure (well almost).

 

Powerglides are so easy that one of my fellow racers down in Ga. rebuilt his on the tailgate of his pickup in the pits at the track. He replaced clutches and band in about an hour.
Still raced that night. He did them for a living during the week so it was second nature to him.
He cleaned everything with brake cleaner.

 

I spent a few years in the Transmission shop of the heavy equipment dealer I worked for. I rebuilt hundreds of power shift transmission (basically automatic transmissions used in off road heavy earth moving equipment). Each transmission contained hundreds of individual parts, all all must be reassembled in the exact correct order. Get something wrong, and it's coming back. And nobody wants a come back. I assume a car automatic is about 10 times easier, but still, each one surely has their own tricks, things you need to know, tools you need to have (buy or make).

We were given about 40 hours to do a full rebuild, and sometimes it was hard to make that. It's a lot of work.

When I started doing them, by the time I finished a transmission I would beg for some physical work, to give my back a work out and to rest my mind for a while. Something like changing the track pads on a dozer; that is just heavy, dirty, grunt work. Pretty soon though, you get used to it, you get familiar with the transmissions, and it's enjoyable work. But that learning curve is steep. Oooofff!

If I was in your shoes, I'd pay the $900, unless the money is too dear. But if you can swing it, that's the direction I'd go.

 

Someone mentioned Badshoe earlier in the thread.
I would purchase his video and see if the project is something you want to tackle.
I used his video, a factory shop manual and Broader Performance parts to do my first AT rebuild on a simple C-6 and it came out great.
Broader knows Ford autos and sells quality parts!
He talks with you and determines your needs and puts all the parts YOU need into your rebuild kit.
It is lot of work.
I tore mine down and looked at all the pieces and thought I had a made a big mistake.
Take one part, like a clutch pack and rebuild it and put it in bag and then another part and than another and pretty soon you just have to stuff all the pieces back in the case.
One more thing, I would not mess mess with the valve body again, I would just order a new one from Broader...

 

the purpose of the hamb is for you to build your entire car by yourself. everyone helps with good information to point you in the right direction. you can do it. i worked next to a transmission builder for 20 years at a ford dealership. it is not that hard to do. it is mostly hard seals and worn clutch plates. you can air check each section and set clearances with a feeler gauge. with books and the internet you can rebuild anything. if you can build a hot rod you can build a transmission.

 

I’ve still got to get it out of the car, then, depending on work, I might have a look inside and see if it’s just a stuck valve. This was a good transmission when it was pulled out, I drove the car that I pulled it and the motor out of a while and it shifted great and didn’t slip, so I don’t think the clutches are to blame. I’m thinking more valve or servo stuck, but I could be wrong, I was one time before. I’m holding on to my money just in case we get real slack in a few weeks, I may need it to eat!

 

Those of you suffering from transphobia should check out PhilA's Mild custom '51 pontiac Chieftan thread. He rebuilds his 4 speed hydramatic. I think most transmission shops would shy away from them since even the old guys there would be too young to have ever done one. Pure inspiration!

 

I'm going to guess a valve body problem . I'm also going to guess there are " exchange" valve body's for sale. Maybe also rebuilt exchange transmissions.

 

Question for H.A.M.B.ers ....what is the most difficult automatic to rebuild?

BamaMav, if you rebuild it and it doesn't work right and you have to then take it to a builder, maybe he can fix your one issue and not charge you the whole $900 . Plus you'll learn something new.

 

an auto trans is full of magical parts and fluids that mysteriously move around and know what to do at exactly the right time. This is also exactly like sausages!

 

I believe childbirth is less complicated!

 

An obstetrician became tired of his job and decided to try something else. Being good with his hands and a closet HAMBer, he decided to try auto mechanics and started by taking some night school classes. In one class, on engines, he got his final exam score of 150%. Pleased, but confused, he went to speak to the instructor.

“I don’t know how I could get 150% on an exam”, ’he said.

“Well”, said the instructor, “ 50% of the test was dismantling the engine and you did that perfectly. Another 50% was reassembling the engine and you also did that perfectly. Then, I had to give you another 50% because in all my years of teaching, I never had a student do all that work through the exhaust pipe.”.

 

that was GREAT!

 

900 isnt a bad deal.
My guy bulilt my AOD using 4r70 stuff, swapped servos for the police car models and a few other internal things. Hell, i have no clue what he did. It has better gear spacing than it used to have, under normal driving it shifts so nice and smooth you could take granny for a ride. Under WOT I'll slam you back in the seat, holds a gear until you think it shouldnt and it bangs it to the next one and just flat hauls ass. I paid him 1400, and got a new converter with that, and once I installed it he sat up the kickdown and lockup cables for me. Like many others, I probably could figure it all out, but why not just pay the man and its done right

 

I read and scanned a lot of the replies and nobody else mentioned it, so here goes.

I would think there's more AODs out there than Model As and flatheads combined. Since we don't see the highways littered with broken down Fords with AODs I'd think it's actually a viable trans in the big picture. What I don't know is if they're all a crap shoot. For instance, you can buy a Turbo 400 from under just about anything, used, and it's likely to give you another 50-100K miles of service as long as it's not abused. AODs the same? I mean there's a shit-ton of those out there, right? Is an AOD worth a grand? $900? $700? $400? Are they as reasonable used as they are plentiful? With a little logic and inspection what's the harm in yanking once from a cheapo used car that you test drove? Getting one from a used parts supplier that offers a decent warranty? Lazy? Not at all, but is it a sound choice? I'm not a whiz kid on such things but we build whole cars out of shit used waaaay longer than perhaps the average AOD. Perspective from your old Uncle Jocko, maybe...