727 Lock up converter choices?

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volaredon

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Please guys. I ain't having any of the "swap in a 904" kind of crap, I've heard plenty.
I have an 85 D150 with a slant in n it. And it has a 727 behind the slant.
Yes I can tell a 904 from a 727. Been at it plenty long enough for that.
I'm about to swap in a fresh slant, slightly hot rodded, hoping to match the power of somewhere between what a stock for the mid 80s 318 would have had, and a stock for 1985 360 would have had, if the truck "would have come with" back in the day. V8s of that era were pretty dismal in power output for what they were. Of all brands. .
Anyway now that the application has been covered, from what the starter has sounded like when I have run it to date on the all original power train, I'm expecting to see a bad spot on the ring gear once I get the original engine out. Meaning that's the time to replace my torque converter anyway.
I also know that without pulling the trans and swapping a bunch of guts with an older 727, this trans is stuck being a Lock up version.
I know that stock they had a low stall and a high stall. How low was low, and how high was high?
I also remember from the last time I was into a torque converter application guide/catalog, that any converter that listed as fitting a slant was also listed as fitting a 727 behind a 318.
That said,. I'd like to have a little more stall, maybe a bit smaller OD converter between the new motor and my existing trans. What is available in a converter for a Lock up 727? Anything besides dead stock?
I was all ready to buy a B&M tork master until I discovered by the PK number that my particular unit is a lock up version. And that particular converter won't work with a lock up. From what I understand that tork master was rated slightly over stock.
For now, until I "prove it to myself"that this power train combo won't be enough for me and for this truck, I want to run with as much of what's already here as I can. Oh yeah in case someone wants to ask it has a 3.21 geared 8-1/4 rear which also stays, at least for now. And tires are 235/75 15s
 
Best to send it out to a place that will open it up and custom work the converter. I had Pro Torque do the original odd splined 904 converter for the wife’s ride.
 
by the time I do that plus have them put a new ring gear onto it (which is the whole reason it needs attention) wouldn't I be better off to just get a different one?
 
I don't know of any performance lockups for a 727 for less than around $500. Seems like asking over a grand is nothing anymore. But a histall lockup would be pretty useful behind a slant. Most histall lockups require heavy duty clutch and billet this and that, so; looking to have yours rebuilt with higher stall might not be a bad idea.
 
CudaFactHackJob said:
I don't know of any performance lockups for a 727 for less than around $500. Seems like asking over a grand is nothing anymore. But a histall lockup would be pretty useful behind a slant. Most histall lockups require heavy duty clutch and billet this and that, so; looking to have yours rebuilt with higher stall might not be a bad idea.
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yikes!
 
volaredon said:
by the time I do that plus have them put a new ring gear onto it (which is the whole reason it needs attention) wouldn't I be better off to just get a different one?
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IF! Is the operative word here. Finding a new lock up converter is not easy. Probably more so now with the way things are in the world and it’s shortages and delays.

IMO, having a knowledgeable guy restall your stock unit is the best and quickest way to go. You already have the main part, the converter! They will open it up and do there thing. Welding a ring gear on is child’s play for such a professional place.
 
The actual stall, in your combo is gonna depend a lot on your cylinder pressure and number of cylinders. So yes a 727 convertor will fit behind either a 318 or a slanty or anything with the right flexplate.
But the stalls will be all over the place, because the stall is a function of the amount of torque going into the TC versus the resistance of the chassis, behind it. and the torque of every engine is directly related to the cylinder pressure and how many pistons it has, firing on every revolution. This is why you can find catalogs listings several stalls with various engines but one part number.

A hi-stall 318 convertor will not be a hi stall behind a low-pressure slanty. But it will be higher than a lo-stall 318 convertor behind thye same slanty . Similarly, a lo-stall slanty TC will stall at a higher rpm when behind a 318, and even higher behind a 360.
Since you are starting with the least number of cylinders, and possibly with a very low cylinder pressure (IDK), you do not have a big off-the-shelf shopping window.
So bottom line is to consult a professional, or send yours out, or cheapest of all .........
 
Don, you have more research to do. A 1988 fsm shows a lock-up converter for 904 and 999 transmissions only. The 727 is a non-lockup only. There is only one stall speed listed. If your trans is working properly, I'd just have a new ring gear installed. And adjust the bands, and change the filter.

Raising the stall speed in a truck is an iffy thing to do, especially if the truck is loaded. Too much slippage creates heat and foaming.

Changing the distributor curve might help. Milling the head might help.

good luck
 
I would take advantage of that lockup by jacking the stall. A 727 behind a slant is overkill, so a lockup would live an easy life. I'd go at least 2500; others would probably recommend 3000-3200.
 
volaredon said:
Please guys. I ain't having any of the "swap in a 904" kind of crap, I've heard plenty.
I have an 85 D150 with a slant in n it. And it has a 727 behind the slant.
Yes I can tell a 904 from a 727. Been at it plenty long enough for that.
I'm about to swap in a fresh slant, slightly hot rodded, hoping to match the power of somewhere between what a stock for the mid 80s 318 would have had, and a stock for 1985 360 would have had, if the truck "would have come with" back in the day. V8s of that era were pretty dismal in power output for what they were. Of all brands. .
Anyway now that the application has been covered, from what the starter has sounded like when I have run it to date on the all original power train, I'm expecting to see a bad spot on the ring gear once I get the original engine out. Meaning that's the time to replace my torque converter anyway.
I also know that without pulling the trans and swapping a bunch of guts with an older 727, this trans is stuck being a Lock up version.
I know that stock they had a low stall and a high stall. How low was low, and how high was high?
I also remember from the last time I was into a torque converter application guide/catalog, that any converter that listed as fitting a slant was also listed as fitting a 727 behind a 318.
That said,. I'd like to have a little more stall, maybe a bit smaller OD converter between the new motor and my existing trans. What is available in a converter for a Lock up 727? Anything besides dead stock?
I was all ready to buy a B&M tork master until I discovered by the PK number that my particular unit is a lock up version. And that particular converter won't work with a lock up. From what I understand that tork master was rated slightly over stock.
For now, until I "prove it to myself"that this power train combo won't be enough for me and for this truck, I want to run with as much of what's already here as I can. Oh yeah in case someone wants to ask it has a 3.21 geared 8-1/4 rear which also stays, at least for now. And tires are 235/75 15s
Click to expand...

I believe the lockup converters for the 518/46rh/46re will interchange if you figure out the internal external balance deal. PATC offers them with a range of stall options. Just keep in mind the stall will be rated for a v8 in those applications so you may want more with the slant.
 
OK... HERE is my SECRET PASSWORD... NOW, CAN I GET SOME ASSISTANCE??
PK4058384 8720 7883. I still do not know WHY this has been made so difficult... I just wanted some info. is that somehow too damn much to ask, around here? It usually hasn't been for me here, to this point. I thought that was the whole reason behind the existence of this website. Info about subjects related to older Chrysler products. Right?
seems like if anyone else asked for info about torque converters available for a lockup 727, and what stall was available, (factory or aftermarket) along with difference in stall RPM between a factory low stall and high stall rated TC they would have gotten a reasonable answer, with much less hassle? Or having to PROVE to anyone else that that was actually what they HAD?
I dont understand the grandstanding and refusal to answer what I asked..... if NOBODY on the forum truly knows, (which I find hard to believe) that would be different.

and BTW I had an 81 W150 with a 318/ and it, too, had a lockup converter..... as did the 1980 4wd 727, that my son got, to put into his 89 Ramcharger... yet the original 727 that was replaced from the Ramcharger, did not. so its not "hard and fast" that "all 19XX year 727s either did/or didn't come with a lockup, after about '78ish....
I am not a trans expert, but give me some credit for knowing something.. I have been around Chrysler products since I can remember, have been inside several of their transmissions over the years, do ALL of my own mechanical work, have never owned anything BUT Chrysler products, in over 35 years of driving and owning vehicles, and work as a fleet mechanic for a living. so cut me some slack here. Or do you possess the ONLY replacement converter, that may suit my needs?

and having done a search on this very site using that PK number, I had hit on someone having had another trans, with this same number on it that they were selling... Imagine that!!!!!! this is not a "one of none" trans!!!
 
volaredon said:
OK... HERE is my SECRET PASSWORD... NOW, CAN I GET SOME ASSISTANCE??
PK4058384 8720 7883. I still do not know WHY this has been made so difficult... I just wanted some info. is that somehow too damn much to ask, around here? It usually hasn't been for me here, to this point. I thought that was the whole reason behind the existence of this website. Info about subjects related to older Chrysler products. Right?
seems like if anyone else asked for info about torque converters available for a lockup 727, and what stall was available, (factory or aftermarket) along with difference in stall RPM between a factory low stall and high stall rated TC they would have gotten a reasonable answer, with much less hassle? Or having to PROVE to anyone else that that was actually what they HAD?
I dont understand the grandstanding and refusal to answer what I asked..... if NOBODY on the forum truly knows, (which I find hard to believe) that would be different.

and BTW I had an 81 W150 with a 318/ and it, too, had a lockup converter..... as did the 1980 4wd 727, that my son got, to put into his 89 Ramcharger... yet the original 727 that was replaced from the Ramcharger, did not. so its not "hard and fast" that "all 19XX year 727s either did/or didn't come with a lockup, after about '78ish....
I am not a trans expert, but give me some credit for knowing something.. I have been around Chrysler products since I can remember, have been inside several of their transmissions over the years, do ALL of my own mechanical work, have never owned anything BUT Chrysler products, in over 35 years of driving and owning vehicles, and work as a fleet mechanic for a living. so cut me some slack here. Or do you possess the ONLY replacement converter, that may suit my needs?

and having done a search on this very site using that PK number, I had hit on someone having had another trans, with this same number on it that they were selling... Imagine that!!!!!! this is not a "one of none" trans!!!
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You got some assistance. I TOLD you who to call. They are probably the best and most reasonable in the country. Did you call them? NO. Now whose fault is THAT? It's a damn PHONE CALL. Now you tell me. Why do YOU have to make it so damed difficult?
 
That number also returns as an 81 non-lockup. Did you check on that ebay link I gave you? But that's a LOCKUP hi-stall converter; might not fit your application.
 
No doubt there Bobby! Did he call any places? Get a price? Finally figure out that LU torque converters are super hard to find and pricey? Grow a brain?

Looks like another to ignore…..

So sorry I couldn’t answer your question to your satisfaction. I tried to help as much as I could. Perhaps you can find me a high stall converter for the older odd spline count 904’s! My crystal ball broke. Perhaps RRR will let me borrow his?
 
rumblefish360 said:
No doubt there Bobby! Did he call any places? Get a price? Finally figure out that LU torque converters are super hard to find and pricey? Grow a brain?

Looks like another to ignore…..

So sorry I couldn’t answer your question to your satisfaction. I tried to help as much as I could. Perhaps you can find me a high stall converter for the older odd spline count 904’s! My crystal ball broke. Perhaps RRR will let me borrow his?
Click to expand...
Naw, the cats knocked mine off the table, remember?
 
Well now nobody said they were so hard to find before now. Maybe now we're getting somewhere

I did look up that eBay link (have it saved even) and I don't remember it saying whether or not it's a high stall version or a low stall version.
Nobody has yet said yet how high is high and how low is low, on these.
 
“No one said it’s hard to find”
So you didn’t even search for one?
If you did, you would have come to this conclusion.
Did you even bother calling a converter company and get a estimate price?
After all, your question was slightly assuming that you would pay big bucks and figured you would be better off with a “New Converter.” Let me tell you that converters aren’t cheap unless there a dead stock replacement or not really worth the money spent, AKA - Junk!

High and low stall is dependent on the engine size and its power of it as well as other factors that change the stall rating of a converter.

Let’s take some arbitrary numbers and use some values that will not actually come to for fruition. Just examples.

A 360 converter stalls @ 1200 behind a mondane everyday mill. Behind a small/medium cam & increased compression increase, it moves up to 1700. Behind a HP big block it’s 1800-2000. The way the numbers work going up with more powerful engines also works in reverse with weaker engines.

Adding weight to the vehicle will increase the stall.
Other factors will add or decrease the stall.

Again, these are not accurate numbers.
 
This information comes from the Dodge truck dealership catalogs. 4058384 transmission with date code 8720 translates to build date June 12 1985. Torque converter part number was 4293065. These numbers were used from 1981 thru 1985. There were no v-8 lock-up high stall converters listed,only low stall. Here is the 1985 description for the 4058384: A727,with long extension, D1 and D2 conventional truck, with 225 engine, with lock-up converter with high stall.
 
townsend said:
This information comes from the Dodge truck dealership catalogs. 4058384 transmission with date code 8720 translates to build date June 12 1985. Torque converter part number was 4293065. These numbers were used from 1981 thru 1985. There were no v-8 lock-up high stall converters listed,only low stall. Here is the 1985 description for the 4058384: A727,with long extension, D1 and D2 conventional truck, with 225 engine, with lock-up converter with high stall.
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Thanks much. That does help a bunch.
And it fits with this trans being there original one from the truck it's in, build date on door jamb says truck was a 6/85 build.
Same month and year I graduated from high school.
So it can't be old yet.
And I simply wanted some info before I started making calls. I will call milt as suggested above, soon as I can. He's on the east coast, different time zone from me. By the time I get home from work it's after 5 "their time" out there.
I do have a trans parts warehouse that I've bought from in years past, that I'll be calling as soon as I get to take off a lil early so I can make it up there before closing, they're 2 hours away from work with good traffic.
There are no stickers on the front face of the converter. I've seen those before. So then as they go I should have the higher stall version in there now.
And yeah I did see a few rounded over teeth on the ring gear so yeah I will be replacing it with the engine swap.
 
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