727 transmission swap to newer overdrive transmission

[dougs23rb]

Sent: 9/18/2004 9:05 AM

I have a 1976 23RB Minnie with a 360, 4:56 gears, 16.5 wheels, 2bbl carb, dual exhaust with 65,000 miles. I will be replacing the 3 speed 727 torqueflite with a 1994 A518 out of a full size Ram van also with a 360. The A518 is essentially the 727 with OD in the tail housing. I have some experience with the 727 to A518 hot rod swaps so this should work. I also have a set-up of adjustable vacuum switches along with a master trans control switch that will allow me full control of converter and OD functions but also allow the engine manifold vacuum, or lack of it, to kick the converter out and then OD out as needed. About Dodge trans durability; The 727 (and the newer OD version), doesn't have the ability to charge the converter when in park or neutral, only in drive or reverse. Utility companies that idle for hours drop their Dodge tranny's in 20 to 30,000 miles. There is an in the vehicle fix however. Let me know if anyone is interested, I'll post about this swap. These tranny's are super tough. I've ran them behind 500hp without a problem! 

[Sea Hag]

Sent: 9/18/2004 9:50 AM

Let us know how it goes . There are many discussions on over drive units and trans w/over drive  swap possibilities .  Do note that these are A727 Load Flight transmissions , a heavy service version of the Torque Flight . Not sure if the load flight was installed in chassis with less than a 1 ton rating  - Sea Hag 

[dougs23rb]

Sent: 9/18/2004 10:38 AM

I'm not familiar with the Load Flight trans but I'll look into it. A heavier version of the A518 dubbed the A618 was made for the diesel Ram trucks. Just added another clutch plate to each pack and I think they beefed the converter. Stock lock up converter has a somewhat light clutch disc of .090. But if the lock up and OD are used for level cruise at over 2000 rpm and 40 mph or more she'll do just fine....I hope. I'll keep ya'll posted.

[Oz]

Sent: 9/18/2004 10:43 AM

Good to see we have a member with experience in this, Doug!  Like Sea Hag said, this has been a topic of discussion an a few occasions. 

Always searching for ways to improve mileage and performance, this swap has been a consideration on many CWM minds so, there's no doubt, just about everyone is interested!  Your expertise is greatly valued.  It would benefit us all if you would be gracious enough to identify what engines the swap will work with, what modifications need to be done, the process, anything of special note in the process, the cost, and the problem/fix you mentioned.  Also, any driving practices which we may need to be aware of to avoid damaging the system.  A lot of us are self-taught, backyard mechanics with slow learning curves (myself having the widest curve of all) so we would appreciate all you have to say.

[dougs23rb]

Sent: 9/18/2004 11:58 AM

Gas is still going up. OD seems like the logical fix. I have done this swap before in cars. It makes dramatic improvements in mileage and noise, wear etc...

The real trick will be if the .69 drop the A518 OD affords is too much for our weight causing such a low manifold pressure that the added load results in a marginal mpg increase at best. I'm a small block guy so I just did a little investigating and I think that the big block 727 (my be that load flight trans Sea Hag mentioned) is ..well...bigger than the small block 727 and the 4 speed A518. But that's not a problem. An adapter plate is available to install one of these later small block 4 speed auto's to that big block. Plate is going to add about 540.00 to the cost of the swap for you big iron guys. But...big block 440 guys can also have their choice of GM's 700R4 using a swap plate. That trans is abundant and the OD is .78 I think.  I can't do that with a 360 or 318. By the way 318 engines are internally balanced so ya gotta knock the balance weights off the converter before you start. 

Add on OD, ie...Gear Vendors units will cost you $3000 by the time you get it, cut down the shaft and wire it up. I just bought the A518 for this project for $400.00 with converter. It came out of a passenger van that appeared to be clean and was without evidence of a hitch. The yard let me pull the pan..(I know them)..and she was as clean as could be. Even with the odometer reading 110,000 miles I will not need to overhaul. As I said in prior posting, it's the delivery truck that idles a lot that kills these tranny's. 727's have that lube problem too.

Don't idle too long unless you are in gear. (fixable) Otherwise these tranny's are bullet proof. The switches you use depend upon the level of control you desire. I use a master trans control switch. Illuminated they cost a couple of bucks. I then use one more for the converter override and yet another for OD override. Different colors...cool. I also install two adjustable vacum switches. One at a relatively high manifold vacuum or light throttle, holds the converter unlocked anytime I start to pull much of a load. I'll adjust it as needed once installed so it doesn't hunt. The other vacuum switch kicks the OD out but at an even lower pressure. I'll start with 6 or 7 inches of vacuum. A panic full throttle application on the highway instantly gives me the stock 1 to 1 third gear. Both switches then allow the circuits to re-engage once the load is off. Simple enough.

I will also wire the main trans control to the brake light switch. This time I'll try to do that with an electro mechanical switch so I will have to re-engage manually once I touch the brake. You can actually engage the OD once you are out of 1st and use it like a high low range. Just takes human intervention. But, you can trash a trans if you engage that converter with a manual switch, no vac override, and just forget! If there is a weak link it is the converter. So priced out it looks a bit like this. $400 to $800 for a trans, $150.00 for wire and switches...I like lots of switches..$80.00 to cut and balance the drive shaft and if you want to fix the lube at idle problem and improve the shifts add another $60.00. Add $540 for the 440 adapter. (and that could be less if shopped! There are a couple out there.) I'll do some pics. I'll start next week. Thanks for the interest. I hope to see a couple of extra mpg but I also enjoy the lower rpm.

I'm not really an expert I just ask a lot from experts and tinker until I get things to work.

PS:
Chrysler makes a smaller 4 speed. The A500. It is the 904 size. The A518 is the 727. The A500 will last for one trip around the block in one of our beloved motorhomes. Don't get them confused!


Here is a great trans site for vac switches and adapter plates.
http://www.transmissioncenter.net/dodge.htm
Scroll way down to about 85% for the adapter plates.

[Sea Hag]

Sent: 9/19/2004 11:42 AM

Doug , there is a very detailed section on the A727 load flight in the dodge chassis sevice manual . I may be able to get some info to you if you email .  I don't plan to upgrade my trans as long as it's still good . More millage would be nice , always looking for options , should my trans fail . And always interested in what modifications other members have done  and what works . Sea Hag 

[dougs23rb]

Sent: 9/19/2004 12:54 PM

Sea Hag, I just might take you up on that info but first I'll check with a buddy of mine that worked at the Kokomo Indiana trans plant for Chrysler. This guy can look at a clutch drum and tell you which trans it came out of. I can tell you that the A518 main trans is one tuff unit. (until she idles in neutral at least.)

That Load Flight might be the equal to the A618. That's what Chrysler did to beef up the later diesel truck. But note that they did put the A518 behind the early diesel without any trouble. The newer Cummings does put out serious torque now so I guess with the long warranty, extra torque and Allison as a competitor, they put one additional clutch in each drum as insurance.

I can hardly wait to get this installed and see just what the mpg does. I get 10.8 at 60mph now. I'd like to see 12 to 13 with less noise, heat and wear. Getting started next week. Worst case; Leave the converter unlocked, keep it out of OD. I'll still have the same three first gears. Kinda expensive experiment however.

[kevsws6]

Sent: 9/19/2004 4:50 PM

I would really like to see one of these swaps work. I wont chance it cause I'm chicken. We can all use 1 more gear. Keep us up to date.

[Sea Hag]

Sent: 9/20/2004 9:28 AM

Doug , Ok I have the info any time you need . I have the 440 3 and would kill to get 10.8 mpg . Not sure I'm getting more than 6.5 right now but I have a heavy foot , I think it did better when my son drove . I'll start with a carb rebuild this winter first and go from there . Maybe add a shift kit , if needed when I change the trans oil , filter and adjust the bands .

According  to the chassis Parts catalog 69-77  the A727 trans went through several modifications  and upgrades . you have to go by the trans serial number to know which parts you need .  I haven't seen to many posts on trans problems so it seems to be a very solid unit . I know the Torque Flights were , especially for racing in the good old MORE POWER days . Sea Hag 

[dougs23rb]

Sent: 9/29/2004 8:15 PM

We started our trans swap today as promised in my 09/20 discussion. My 1976 van chassis with 727 trans mount is not wide enough for the new overdrive A518 but not to worry. A late model full size van trans cradle will solve this problem. We did have to modify one floor reinforcement but not a difficult task. Cost of the new trans mount (bone yard) is $25.00. I forgot my camera but I will take pictures and report back to you all as this project unfolds. Stay tuned.

[dougs23rb]

Sent: 10/1/2004 9:46 PM

My old coach now has an A518 or 46RH 4 speed  automatic overdrive installed. I wanted to get the overdrive trans actually bolted up to measure for the drive shaft shortening. The shaft will get shortened on Monday and will be installed most likely on Tuesday. The cradle (rear of trans) from a late model full size van needed only very minor modification. Two tabs bent over 180 degrees and she bolted right up. I used the existing kick down lever from the old (727) trans on the new trans and all other linkage fit perfectly. Cooling lines and neutral safety switch pigtails are the same. The floor support directly above the OD unit required some 2" height by 8" long notch be cut out. We boxed that back in and undercoated it. That has been the only fabrication that the average weekender might have a problem with unless he can weld. It might be OK to just cut it out and not box it in. I'll install the lock up and OD switches this weekend. By Wednesday I'll be test driving. Total cost to date including the trans; $400, flex plate; $25, brackets and isolator; $37 and switches; $85 is: $547.00. Another $87 gets the shaft cut and balanced so I should be done for $634.00. I'll break even money until about 20,000 miles but I'll enjoy the lower RPM's sometime about mile.......1 !!!

[Oz]

Sent: 10/3/2004 2:13 PM

Not as bad a cost as I would have thought, Doug.  Thanks for letting us know the price tag and giving us the details.  Sounds like a good 360 up-grade.  The proof will be in the longevity test... time will tell but, I think you got it on the money.  Any input as to the possibility of this up-grade for us vast majority of 440 owners? 

[dougs23rb]

Sent: 10/3/2004 9:00 PM

The longevity issue can only be tested in due time, you are absolutely correct. The A518 is however, considered a heavy duty transmission. I've stuck these A518's behind a 500 HP 383. It doesn't get the constant strain of a 440 motorhome but other gear heads I converse with seem to think as long as the lock-up convertor isn't used and the overdrive isn't engaged under heavy load, it will last. I think you guys are under heavy load all the time and therefore the amount of time when you really could use the OD will so limited that it will be of much less value to you. But Dodge makes a super duty version of the A518 dubbed the A618. They put that behind the diesel and the V10. No doubt in my mind it will hold up.

It's the same size as your basic 727 but it will not be so easy to control the shift points. And the cost of a good used one almost makes the gear vendors OD unit attractive. And that...is pretty ugly. Drive shaft gets cut Monday, installed Tuesday evening and the big test drive is planned for Wednesday eve.

There is an ebay player, Phoenix Reman Transmissions, with A618's and a buy it now price of $895.00. Not too bad. Core charge isn't listed but I'll bet it's healthy.

[Jlogue88]

Sent: 10/4/2004 4:46 PM

Don't forget it would have to be a pre 94 tranny or you will have to deal with the electronics and computers to make it work.

[dougs23rb]

Sent: 10/6/2004 10:10 PM

My 1976 Minnie now has overdrive! I haven't put it thru the mill yet. Just drove around the industrial park and manually energized both the OD and the lock-up. No leaks. No noises. I'll stomp her good this weekend and let everyone know how she does. About the 1994 or earlier. I learn something new everyday. I'm not real sure about the latest years but my 1994 A518 has an electric solenoid for both the lock-up and the OD. It has a three wire pigtail. But by using the vac switches and oil pressure switch (governor pressure) you can make the A518 work like it was still hooked up to the computer. Could be different now, I agree. The biggest problem I had to learn to deal with was due to the externally balanced early engine and getting the correct combo of torque converter and flexplate for your new trans. It gets gooffy. But it's all in the fun!

[dougs23rb]

Sent: 10/10/2004 11:19 AM

I can only describe the results of my overdrive upgrade as "utterly pleasant"!

I have only been able to check the mileage on a 20 mile run on Indiana level highway but at 60 MPH it came in at 13! No load. No wind. No hills. Not even a ramp to climb. The converter was locked up and overdrive engaged. RPM at 60 without the lock up converter engaged is -3000. Converter engaged gives me 2750. OD engaged just above 2000. I don't have a good vacuum gauge installed but on level hwy it doesn't seem to be lugging. The unit I have is both vac and boost and it sticks. However, performance seems good. Light throttle gets the converter unlocked and that acts like a gear itself. I put manual override switches on each function so that I could bypass the vacuum and governor pressure devices.

Eastern and Southern Indiana have a few stretches with good grade. I'll see what it does then. I'm about to acquire an estate motorhome. (I think I am anyway) It's a behemoth I'm guessing 30 footer, mid seventies CruiseAir with a 440. Unless it has a Gear Vendors in it now, I have my sights on another swap. That one will get the extra clutch disc in the OD unit. (A618). 

[uglydukwling]

I have a '78 Elandan II in which the original 440 has been replaced by a 6-354 Perkins. It still has the original Load-Flight (big-block bolt pattern I presume, with an adaptor plate to match the Perkins). The Perkins reaches its limit at 2500 rpm, which gives me almost 50 mph. So it definitely needs an overdrive. The prervious owner solved the problem by installing a divorced Gear Vendors' overdrive. It was ideal until the sun gear exploded. Now I'm loking for alternatives. No matter what I do, including a new Gear Vendors', I'm going to have to modfy drive shafts, so maybe this is the time to replace the transmission with an overdrive.
It looks like there never was a version of the 518/618 to fit the big block. I have a '93 Dodge with a Cummins and automatic (518?/618?) but I've heard that the bolt pattern is unique to that engine so, even if I wanted to spend $500+ for a small-block to big-block adaptor, it still wouldn't work. I don't really like the idea of stacking adaptors, anyway.
I suppose I could have an adaptor custom-made to mate the Perkins to the transmission. What else would I need to make them fit each other?
If  I forget about using the 518/618, does anybody know about any transmisssion that will bolt directly to the Perkins? I have no objection to a manual trans (Eaton 10-speed, anyone?), but the clutch and shift linkages are likely to be a can of worms, so I'd better stick to automatics.
I've even thought about putting the Cummins and its transmission into the Winnie as a unit. At least I'd have a combination that was compatible from the factory. But, looking at how much trouble somone went to, to make the Perkins fit, I don't really want to start over with a whole new list of things that don't quite fit. Also, I know the Perkins is in good shape, and I really don't know much about the Cummins, except that it has a few hundred thousand more miles on it than the Perkins.
Any suggestions?

[Elandan2]

A Perkins 354?  Shouldn't this be in the JOHN DEERE section?     That sounds like an interesting conversion.  Any pictures?  Rick

[Alaskan Rodgers]

I'm also interested in the 354 Turbo Perkins Diesel conversion to a Dodge Winnebago Brave D 18 with a 318 V8. How well did your 354 Perkins do going up a grade in the mountains? What was the mileage like? Did you find The right overdrive transmission?

[LJ-TJ]

Everything you ever wanted to know about converting to a Diesel.

http://www.classicwinnebagos.com/forum/index.php/topic,6699.msg27938.html#msg27938

[uglydukwling]

The Perkins hasn't been near the mountains (at least since I've owned it). Acceleration is nothing to brag about, so I suspect it might have trouble with really steep grades. After all, it has about 100 hp less than the 440. It would probably be a more appropriate replacement for a 318, but I have no idea how much trouble it would be to make it fit.

With the overdrive, it would cruise at freeway speeds, but now it's too slow. I haven't installed an overdrive yet. I have a Spicer auxiliary overdrive transmission I'll probably end up using, but it's big and heavy and won't give me as tall an overdrive as the Gear Vendors, so I've been holding off, hoping something more suitable turns up. Meanwhile, I just stay off freeways as much as I can. Secondary highways are more fun anyway.

As far as fuel consumption, I was getting about 12 mpg, translated into American. It doesn't seem to have gotten much worse without the overdrive, but then I'm not going as fast. With a smaller rig, you should get better mileage, but you won't know how much better until you try.

[GONMAD]

Greetings All!    This sounds like a good (AND LESS EXPENSIVE) approach to a common malady for ALL RVers.  I wonder if Trans-Dapt makes an adapter for this type of swap. It could be the solution for many as I had a hard time parting with the $3300.00 it took to acquire my Gear vendors, & i must say,
  "This should be THE FIRST mod for pretty much any older RV" (INSTEAD OF THE LAST).
  I'll be looking forward on your results in this endeavor, Good luck & best wishes to All.      GONMAD

[Licksquidink1]

House that swap working out? still good? Hey, you run a 360 - 2 (two) barrel,Is that right?