Just wondering on this one. Is the overdrive the weakest part of the 518? The overdrive unit bolts on to the tailshaft housing, correct? I want to build a shortbed race truck one of these days, and a local guy has a 518 for sale, but I would like to use a 727. Am I the only one that would rather have an auto than the getrag?

 

Everybody would rather have an auto, some people just don't see the light, however.

I'd like to know what the internal-mechanical differences between the A-727, A-518 and 47re (or even the 48re) are.

As far as I can tell, the mechanicals between all of them are the same, only the 727's have a much better reputation than all of the designs that are based off of it...

 

You cannot just "remove" the OD section. That tranny can be built to hold a ton of power, so I say just go for it!! If you need an old school 727 let me know.

 

But there's no reason why you can't wire a switch to lock out the overdrive section when you don't want it, correct?

Just having the overdrive in there doesn't rob any power-holding capacity, right?

 

It's hard to say, you can just lock out OD, very easily--but, you have an extra shaft to turn, and more clutches, etc. Will it make a real difference??? I don't know.

 

If there isn't any mechanical difference, I would love to get a 47re, with a lock-up TC and overdrive, to replace my 727. Overdrive and lock-up with a 3.07 rear end would probably let the truck idle at freeway speeds.

I just find it strange that the 727 has such a reputation as a bulletproof tranny but people treat the A-518/618 like herpes.


Jughead (or other tranny expert), we need you're experience.

 

I don't consider myself an expert, but I'm not completely clueless either. I would stick to a 47RH in a 1st gen (like what I did), leave the RE for the 96 and up 2nd gen guys.

I had a nightmare with a trans shop with my 47RH and the problems boiled down to poorly built torque converters with high stall speeds and a crappy job on a valve body causing all sorts of problems. The most notiable one was lockup for no reason in reverse at part throttle.
The fix: Gorenend converter and valvebody. Fixed it right up.

 

just got my summit mag in yesterday. they have strong 727's in the $750-$1200 range

 

For a diesel? Remember the gas 727 is a completely different case. And the internal parts are probably lighter/smaller that their diesel counter parts. Not to mention the torque converter is larger and has a lower stall speed for the diesel.

 

I think that the RH stands for Hydraulically controlled and RE stands for Electronically controlled... They both are equally strong though, correct? If the RH is more of a self-contained unit, then I guess I'd want one of those.

But I still can't find the strength differences between 727 to 48re... As far as I can tell they are virtually identical.

 

oops, yeah, they were gas

 

The 48 is stronger than the old 727, it is presumed weaker due to failures under HUGE amounts of torque that the 727 never say with a gas engine. And maybe once in a while it did, but it was way up in the RPM band.

 

Might want to check out the parts at this link:

http://www.transmissioncenter.net/dodge.htm

Don't know how competitive the pricing is and have never dealt with them, but they've got the stuff!

 

one of the nice things about a 727 is that the shaft is not Gun drilled to get lube to the overdrive section, This makes it cheaper to build and much stronger!!!!!! I think 727's are awsome!!!!! Especially if you want to play!!!