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727 troubles

Bradyc32

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Hi all. Getting ready to start working on my '76 with a 400ci v8 and a727. Transmission is toast and wanting some advice on whether I should buy a reman transmission or get the one that's currently in the truck rebuilt. Also, does anyone know what the difference is between these two options? Specifically, the "Ext House Len" option. Picture is from jasper engines website.

jasper.png
 
If you've got the tools & know-how, rebuild it yourself, like volaredon said. You would save a TON of money too, rather than on someone else doing it, shipping & all that. Just by the looks of the advertisement, I'd think one is for a 4WD & one is 2WD. Different tail housings. If you're going the re-man route, have YOURS done. Make sure you get a new convertor & flush your trans cooling lines & radiator cooler. Adding an additional external trans. cooler is a very good idea too.
 
Thanks for y'all's advice, I will consider rebuilding it myself. Is there a certain type of rebuild kit I should be looking at?
 
Rebuild kits don't come with bands or steel clutch disk. Other than that everything should be in a kit. Get a good set of snap ring pliers. The rest can be improvise.
 
A 3sp is a lot easier than the modern 4,5,6,8 and10 speed trans. Get a book about the 727 or watch YouTube videos
 
Rebuild kits don't come with bands or steel clutch disk. Other than that everything should be in a kit. Get a good set of snap ring pliers. The rest can be improvise.
I did some looking and it says this deluxe kit from rock auto has bands and a steel clutch plate. Will that work?
1743294584303.png
 
A 3sp is a lot easier than the modern 4,5,6,8 and10 speed trans. Get a book about the 727 or watch YouTube videos
Yep, I'll be sure to do a lot of reading up and watching other folks do it before I attempt mine.
 
Rebuild kits don't come with bands or steel clutch disk. Other than that everything should be in a kit. Get a good set of snap ring pliers. The rest can be improvise.
No bands with the kits but they aren't that much $$$.
And just a basic "rebuild kit" is just the gaskets and seals. Then up the ladder is the "banner" kit which I think comes with clutch discs but no steels. Next step does have the steels. And that's the kits I buy. Brass thrust washers is another kit as are the brass bushings which are a "replace as needed" thing as are the snap rings.
I just did a 46 RE ( front half basically is a 727) and have a 42RH (A500) apart right now.
 
No bands with the kits but they aren't that much $$$.
And just a basic "rebuild kit" is just the gaskets and seals. Then up the ladder is the "banner" kit which I think comes with clutch discs but no steels. Next step does have the steels. And that's the kits I buy. Brass thrust washers is another kit as are the brass bushings which are a "replace as needed" thing as are the snap rings.
I just did a 46 RE ( front half basically is a 727) and have a 42RH (A500) apart right now.
Did you leave the 46 RE basically stock or go with the 4 planetary billet 1- R drum?
Have you ever beefed up the od unit?
Will be into my first 46 in a week or two.
I have gone threw plenty of 727's.
 
mine had the 4 planetary one in it already.... not really done much with the OD section, as the paper I got with my shift kit said something about drilling a couple of oil passages in the output shaft from (I think it was) 1/8 to 3/16 (whatever it was it was 50% diameter increase) as I never found a drill bit that would touch that material the output was made of.... Ive tried. the problems with mine have rarely been in teh OD unit... broken 3-4 accumulator spring in the valve body, smoked rear clutch in front housing, etc... I do like the Superior (and/or Sonnax) HD accumulator and servo's/ I put them in this one. the original accumulator was (ugh) plastic.... and the replacement (aftermarket) ones have double sealing rings as well....
just got my tailshaft back from machine shop for the 42RH, , I busted the bolt holding the speedo adapter in, and ended up drilling off center and breaking a reverse (LH) drill bit off in it trying to fish it out.... first time I've ever had one of those break...
Actually, I'm building this A500 to go behind a slant 6 in an 85 D150 of all things.... and yes you can put a trans for a SB behind a /6 even though the bolt pattern is different... Back in the 60s (til 68 or 9) they never "made" a 727 for a /6..... before they created and cast a /6 specific 727 case they put a roughly 1" thick adapter on the /6 to mate them.... along with a same thickness spacer for the butt of the crank to space out the flexplate. Every '60s truck, A100 van, police or taxi that had a /6 and auto trans had the 727 with this setup. Hard to find these days. I bought a whole '64, /6 and 727 just for that adapter..... and sold off the motor and the trans seperately once I had what I needed.... the trans I'm building came out of a rotted out 91 Dakota, w/a 318....
 
mine had the 4 planetary one in it already.... not really done much with the OD section, as the paper I got with my shift kit said something about drilling a couple of oil passages in the output shaft from (I think it was) 1/8 to 3/16 (whatever it was it was 50% diameter increase) as I never found a drill bit that would touch that material the output was made of.... Ive tried. the problems with mine have rarely been in teh OD unit... broken 3-4 accumulator spring in the valve body, smoked rear clutch in front housing, etc... I do like the Superior (and/or Sonnax) HD accumulator and servo's/ I put them in this one. the original accumulator was (ugh) plastic.... and the replacement (aftermarket) ones have double sealing rings as well....
just got my tailshaft back from machine shop for the 42RH, , I busted the bolt holding the speedo adapter in, and ended up drilling off center and breaking a reverse (LH) drill bit off in it trying to fish it out.... first time I've ever had one of those break...
Actually, I'm building this A500 to go behind a slant 6 in an 85 D150 of all things.... and yes you can put a trans for a SB behind a /6 even though the bolt pattern is different... Back in the 60s (til 68 or 9) they never "made" a 727 for a /6..... before they created and cast a /6 specific 727 case they put a roughly 1" thick adapter on the /6 to mate them.... along with a same thickness spacer for the butt of the crank to space out the flexplate. Every '60s truck, A100 van, police or taxi that had a /6 and auto trans had the 727 with this setup. Hard to find these days. I bought a whole '64, /6 and 727 just for that adapter..... and sold off the motor and the trans seperately once I had what I needed.... the trans I'm building came out of a rotted out 91 Dakota, w/a 318....
Thanks for the info. Haven't gotten into the trans yet. Even though I have four plantery units whole buying new billet isn't that expensive. Have yet to see plastic parts in a 727 so this 518 based will be a new experience.
 
The only plastic in my 46re was the accumulator, a plastic spacer ring behind the snap ring holding the Belleville spring in the rear clutch (front housing ) and the "carrier" for the springs and rollers in the sprag that's in the OD housing. The 500 I have apart now didn't have the spacer in the rear clutch pack, but had the carrier for the sprag in the back of the front housing as plastic.
This would be the same sprag that's in the 904/727 behind the low/reverse drum
 
I have been using the bolt in sprags for years. No worries about one spinning in the case. I also have a box full of good old metal parts.
 
I've never had issues with a sprag in one.
I've replaced the last few with plastic carriers though. I may leave the one in the OD alone this time though just because I can't find the 2nd one that I bought when I did the last one knowing that I had this one under the bench next in line to go thru...
 
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