BeepBeepRR
Well-Known Member
My trans that was in the roadrunner is a 69 the RV trans is a 75 Im not sure myself if they will swap. But im gonna find out.
Motor home 727
- Thread starter bearman
- Start date
mopar 3 B
Well-Known Member
I will check the trans bible
The only thing you really need is to make sure you have a 4 friction front clutch. The RR trans will have a higher upshift governor. As far as the planeteries? What would you say if i told you these cars all run 3 pin. 11.0@3900, 10.0@3400, 9.50@3750 turbo w/trans brake 9.0@330lb car. 4 pin are unnecesary. Easy to make a 727 live behind 700hp with stock parts and a good valve body.
Doug
Doug
BeepBeepRR
Well-Known Member
Good to know. I know something broke in the RR trans just never opened it up to figure out what it was. The front part of the case looks like it ejected a torque converter bolt out the bottom at some point. So there is a hole in the case. That's the only reason I'm even thinking about the RV case.
Rv case is fine. Hole in bell housing hurts nothing. The 1971 and reaction shaft support (back half of the pump) and drum feature the wide bushing which is nice. Keep the early thin pin servo and shim it solid with an extra input/output thrust washer. See if either lever is a 3.8.
Doug
Doug
BeepBeepRR
Well-Known Member
When the trans was still in the roadrunner. I put it into reverse and heard a tin pop sound. Kinda like something hitting the trans pan. Then it wouldnt shift into forward gears. Im thinking the band adjuster may have either fallen apart or that bar broke. The one that goes from the adjuster to the band. Never looked further into it. Just bought a new trans. I would have taken it to a local trans shop but I have nothing but bad reviews of most of the moron mechanics around here. PLus a few bad experiences myself. Thus the need to do this myself. I can trust my work.
That's why I learned to do my own. Over 35 tears now. Get Carl Munroes book or factory service manual. Ask questions. As far as what you've stated in your RR trans. Bands don't control any foward gear except 2nd and 1st on coast down only. If it has reverse and no forward the likely suspect would be the back clutch. However with the snap noise it may have failed a hard part (rare).
Doug
Doug
BeepBeepRR
Well-Known Member
The transmission was said to have been rebuilt. When looking at the out side of the case it does look like at some point it was run through a bake/clean process. To be honest I cant remember what exactly it did when I heard the tink.. Now that I think about it I did drive it around the block. But was in fear of further failure. So it may not be what I was thinking. That was over a year ago. I just need to get the fat *** trans up on my bench. I'm a little dude so trying to get it up there by myself is a struggle. I guess I could take my hoist out to the shed. Probably the easiest way. So I have to retract my previous statement about not going into forward gears.
If the roadrunner trans is an easy or cheap fix I'll just do that and leave it as is. And just sell the RV trans to the first person who needs an awesome transmission for their swap. The RV was said to have only had 47k on it. I pulled the trans dipstick and the fluid looked like it was newish. Not burnt or anything.
If the roadrunner trans is an easy or cheap fix I'll just do that and leave it as is. And just sell the RV trans to the first person who needs an awesome transmission for their swap. The RV was said to have only had 47k on it. I pulled the trans dipstick and the fluid looked like it was newish. Not burnt or anything.
Last edited:
bearman
Well-Known Member
sorry about late return just caught up in life things but anyways the rv trans is a 78 model and don't have a doner as of yet. talk to my trans man and looking for the new tail shaft etc to bolt to rv trans. this is a first for me so we will see how it goes.
mopar 3 B
Well-Known Member
Output shaft and front planet pinion carriers were changed in 76. What this means is you would have to find a third trans 76 or newer to salvage the output shaft from to utilize the 78 motor home trans.
Tail shaft case would work off your old trans. But why you would want to use it after the buying the third trans.
Internal 727 parts are not that expensive unless going with race parts. Buy time you replace all the parts for the 78 trans you could rebuild the original.
Tail shaft case would work off your old trans. But why you would want to use it after the buying the third trans.
Internal 727 parts are not that expensive unless going with race parts. Buy time you replace all the parts for the 78 trans you could rebuild the original.
bearman
Well-Known Member
that is good to know and maybe the best thing to do is look that way. the engine is going to be a mild build and a 6pac with the right converter and shift kit and looking at 3.55 gears i think i will be ok on the street.
bearman
Well-Known Member
what are your thoughts on tci etc type trans is it just name or really built for our needs. i think the biggest thing is to get the converter correct or am i just in the unknown. back in the day i was all about buying aftermarket trans so you could say you had this and that but being old now stickers are not my thing. looking for best to do what i need from it of course i will have trans cooler and syn oil etc to maintain it. but then i worry about some local building it with junk parts etc maybe the best thing to do is just find all the right parts and do it myself that way if something goes wrong its on me. plus i will be learning something from it i could find a car trans rebuild it the way i need it and move on.
mopar 3 B
Well-Known Member
- still have the original?
BeepBeepRR
Well-Known Member
Bought a Hughes Performance Trans for the Roadrunner. It had a leak around the pump but Hughes being stand up people they are paid for return shipping fixed it dyno tested it and returned it with a case of Lucas sure shift fluid and a nice Hughes T-shirt. They are right there in Phoenix. I bought it through Jegs I think it was 1300 bucks. It would not leak a drop when the car was running. But when you went outside the next morning the trans puked up all its blood. Turned out to be a pump leak. Unseen crack in it.
bearman
Well-Known Member
Well that sucks sorry for your problem. Thats why i would like to do my own build with this rv trans.. never had one completely apart but always willing to learn. I was hoping loke i said to switch out tail shaft and get the converter and put a shift kit in and be good to go. Well it sounds like more to using the rv then i thought what was going to be a easy fix up may not. Mine being a 78 model was told to use 76 and newer to make things work which i will go look for that and get pricing i guess what im trying to do is cost the same to redo all this or just get one thats done with a warranty for any problems.
mopar 3 B
Well-Known Member
All you need is the output and tail shaft form a 76 or newer 727 big or small block.
But before you get totally discouraged what is the number on the pan rail on the drivers side infront of the shift fork with it I can confirm the transmission date.
If the engine is out of a 78 motorhome it may not be of that year. Our 77 class C sits on a 76 dodge van chassis. If you pulled that from a class A the engine and trans could be what ever was available when it was built.
But before you get totally discouraged what is the number on the pan rail on the drivers side infront of the shift fork with it I can confirm the transmission date.
If the engine is out of a 78 motorhome it may not be of that year. Our 77 class C sits on a 76 dodge van chassis. If you pulled that from a class A the engine and trans could be what ever was available when it was built.
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