Lockup converter in a first gen?

[paccool]

OK, here's something I have been wondering about for some time. I'm not sure how the lockup section on a torque converter is controlled so thought I'd ask.



First off, is the lockup done electrically or hydraulically? If done hydraulically, forget this already. If done electrically, could a switch be rigged to turn the converter lockup on? Something like the cruise where if you tap the brake pedal it would turn off. Maybe a switch that could be triggered off the TPS voltage thru a relay or diode control system where the thing would not lock up until there is 2. 5 volts or so. I'm not trying to reinvent the wheel here, just trying to figure out if it's possible.



Now, if it is possible, will a second gen converter fit on a first gen transmission?



Any ideas?

 

[dan brooks]

I'm really wanting a lockup converter, too - after going over Monitor Pass in CA during my vacation I really think an exhaust brake is needed. :--)



My understanding is that the "lock" in the converter is activated hydraulically, and there is an electrical solenoid on the valve body that opens the passage to the converter. I don't know if there are differences in the trans case or pump between lockup/non-lockup transmissions, or if you can just swap in a later model valve body.



If I come up with a good deal on a later model "RH" trans I'll probably swap it in, then use a toggle switch on the dash to lock the converter. We did a manual to auto swap on a friend's Jeep, using a TF999 (3-sp auto w/lockup), and he uses a switch to lock the converter once he hits 3rd gear. After driving it for a while he said it's second nature to lock/unlock the converter, but - in the TF999 at least - the converter will not lock in 1st gear, so if he forgets to hit the switch when coming to a stop the trans will unlock on its own and not stall.



I read somewhere that there may be a "stand alone" computer on the market in the near future, allowing an even later model "RE" trans to be used..... can't remember where I saw that, though.

 

[bvanetten]

I put a 47rh transmission behind my 205. I have switches for OD and lockup. It's getting kinda old having to switch all of the time. You should do a search on the list... there have been several disscusions about how to automate OD and lockup switching.

 

[BushWakr - RIP]

You can purchase lockup controller from a few different places. My suggestion is obviously a bit biased (see sig. )

Using a manual switch relies on your remembering to swith it off before you try stopping...



Bob.

 

[backroad]

Yes, you can put a lock up converter in a first generation 518. However, there are some things that must be done.



1. Move the transmission back from the engine and extra inch and a half. This can be done by modifying one the factory trans spacers (basically cut the center out of it) and bolt it up with longer bolts. OR, you can use the 94 or newer wider spacer but you also have to change to the new starter.



2. Install the lockup converter of your choice.



3. Install the proper lockup valve body and electrical solenoids and plugs in the transmission.



4. Add a switch to the dash to engage/disengage the lockup converter 'cause the first generation engine control stuff will not do it for you. Read:you have to manually operate the lockup mode.



I wish that I could tell you just how well it works, but I've yet to finish my ford/cummins conversion. Comming close though...

 

[cerberusiam]

This raises an interesting question I have not yet resolved. Can a 518 be made into a 618. Every builder I have talked to says its NOT possible. In all fairness, when asked is they had tried it the answer was no. So, backroad, did you take a true 518 and add a lockup converter, does it work, what had to be changed?



Some lockup systems I have worked used a solenoid on the pump to apply the piston for lockup. It as tied to the valve body to prevent lockup in lower gears and at lower rpms. This would indicate it is possible to swap in the neccessary pieces if there are not any internal passages that need to be present for everything to work right. Once again backroad, any direction on this would be greatly appreciated.



The other sticky point is all the good parts, clutches, drums, plantaries, etc ar in the 47RH an there are several configurations even in that series that has to be considered. Without having the two trans to play with and the lack of detail in the rebuild manuals I am skeptical that interchanging parts will work. If there is anybody that can shed some light on this, please disillusion me.



There are 3 or 4 manufacturers of add on lockup boxes available. They all take inputs from the TPS, speed control, and engine RPM. Its a pick your poison choice.



Stand alone controllers is a great idea but it ain't here yet and not sure with the cost of a good trans I would like to be a beta tester without some hard assurances.

 

[BushWakr - RIP]

cerberusiam,



I won't pretend to be an expert but I believe that when you go with an aftermarket system several things happen.



You will likely use a new/newer transmission case because they are a bit stiffer and less likely to flex. The innards are pretty much all changed to the newer updated RH/RE standards. Larger seals, special accumulators, valve bodies, band struts, etc and much more.

The stock 727 case can be used but it is not as strong and is not worth the HP/Tq that will inevitably flex em to the point of cracking. The OD definitely needs beefing up for use with our low end torque/hp.

Nowadays, I think that the case most often used is the 96/97 vintage.

Since that newer case is used they have no "core" to clean/test/recycle/build. This can add to the costs of a full rebuild.



Bob.

 

[Philip]

My knowledge of the lockup converter on the 618 and higher trans is the apply pressure is sent threw the input shaft. It is drilled for this reason. The 518 runs a solid input shaft.



How did you get apply pressure to the lockup clutch backroad? In your post you said nothing about changing the input shaft.

 

[Joe G.]

You have to use a later model case (47RH) for a couple of reasons. You have to be able to connect the lockup wire to the valve body. This requires a three wire connector: OD, 12 volts, lockup. The 518 probably only has a two wire connector for 12 volts and OD. The 47RE has a connector for more than three wires since it has an electonic governor. You also need a passage in the case from the valve body to the input shaft for the pressure feed to the input shaft for the lockup clutch in the torque convertor.



Does anyone know if a 47RH will fit a '93? Bell housing, flex plate, mounts, length, and output spline?



The switch business can be made easier by using a floor mounted push button to break the ground signal from the dash switch when you want to drop the lockup for a stop or shift. I have it rigged that way on my '95 with a dome light switch. I override the lockup controller so the lockup will hold for my exhaust brake.

 

[cguthrie]

I talked to Clint Cannon of ATS transmissions at May Madness this year and asked him the same question. He said that they could do it but it would be about $6000. They have this thing called a commander that is a switch that engages the lockup at any speed that you want so you don't have to worry about turning it off and on all the time. I also talked to a guy that had one put in his late 91 and he said when he went up there he was going 67 Mph at 1900 rpms across the flats and when he was coming back with the new transmission he was doing 75 at 1900 rpms. Now if i had the money i would have my truck in Colorado right now doing that but that is a little expensive for me, but it still sounds like that would be a great improvement to my truck or any first gen truck.

 

[cerberusiam]

The case flex is a new one that hasn't been brought up yet. It makes sense as some of the problems I have seen are breaking the bell housings. The 47RH from 94 thru the first half of 96 will work for the conversion, but, there are multiple updates and changes in that space also. Specifically to the OD to rectify some design problems. The absolute best core to have is the early 96 or a production run of July 1995 thru December of 1995. That trans had most of the updates and newer parts that were incorporated into the RE when it went into production in Jan of 1996. There may be a few exceptions but anything late 96 and up was an RE. When buying a core you need to check the wiring connector to make sure what it is. The RH wil have a 3 wire oblong connector and the RE has a round 10 wire plug. The problem is finding the RH without having to pay at $1000 for it. All the cores have recycled back thru the wharehouses and it is tough to get one.



The RH will bolt up to a first gen but the converter is deeper to acomodate the lockup. The engine adapter and starter need to be changed for length considerations and the flex plate needs to be swapped for strength and the nose of the converter. The overall lenght is about 1. 5 inches longer so a custom trans/tcase mount has to be built and the drive lines adjusted.



Depending on pump diameters the input shaft and pump could be swapped into a 518 but there are ports on the back of the pump that need to match so everything functions correctly. If the clutch apply pressure comes from the VB then there is no way to make it work. The passages are not there.



The $6000 is about norm for most of the places I have checked with. Half the cost from having to pay a core for the updated trans, the new parts for the motor, and their work to instal it. If one wants to do the work it is still going to push $5000 to get all the needed good parts. Ah well, its only money and ya can't take it with ya.

 

[dan brooks]

Originally posted by cerberusiam



The $6000 is about norm for most of the places I have checked with. Half the cost from having to pay a core for the updated trans, the new parts for the motor, and their work to instal it. If one wants to do the work it is still going to push $5000 to get all the needed good parts. Ah well, its only money and ya can't take it with ya.

Ouch! I guess I won't be putting a lockup trans in my truck. Somewhere down the road I may sell this one so I can pick up a 4X4..... but it'll be a 2nd Generation 12V and will already have a lockup converter.

 

[backroad]

Yes, I did start with a 518 transmission. Yes, I did have to change the input shaft because the splines into the lockup converter are different that those into the standard non-lockup converter. The solenoid/valve body assembly I believe was out of a 47RE, as well as the THREE wire electrical plug from the transmission. OD assembly was beefed up, reshimmed and a couple of other things I didn't understand. The 518 trans is basicallly just a 727 with and overdrive and all of the high tech stuff like the clutches, internal housing and hardened shafts are available through the racing transmission sources.



Remember that the transmission assembly MUST be moved back, whether you double up the early spacer that must be modified OR use the wide spacer from the '94 or newer 47RE that also requires the newer type of starter.



No, I have not yet got to run it, but I've been told that there are quite a number of these lockup conversions running around with perfect success.



Nobody ever said that change was easy or cheap, but there are always certain requirements that have to be met in every application, especially in a conversion. I believe that I have a little over $1600 dollars in the transmission (which was out of the truck and delivered to his bench). I also paid around $400 for the HUGHES lockup converter which is truly not a stock or unproven converter. It includes stuff I don't understand like furnace brazing, much tighter fluid coupling (which is simply put, just a lower stall rating) and a reinforced clutch assembly and special bearings inside. Almost all of this stuff is very Greek to me and I just depend on the people that I've learned to trust in the past.



This conversion also comes very highly recommended by Randy @ Reliable Diesel in Mesa, Az. and the transmission shop (Little Transmissions) that he shares a building with.

 

[cerberusiam]

Backroad, thank you for the wealth of information. I suspected there was a way to use the 518 and upgrade the parts but it is tough without having both pieces side by side to compare. It is practically impossible around here to find a builder that will even talk about any trans behind a Cummins let alone attempt a build on one. What kind of warranty did they give you on the transmission? Do you a phone number and name of the builder? I would surely like to spend a little time conversing with them.



Just the trans cost alone is worth looking at. It is really tough to justify putting almost the cost of the vehicle into a trans unless it is critical. An alternate solution even if it is not quite as beefy as a full boat 47RH would be very attractive.

 

[paccool]

Wow, lots of info here! I was hoping it might be a little easier to do, doesn't sound like something I want to tackle at this time though.



Picking up 8 MPH at the same RPM would be pretty good , should help the mileage a little.



Maybe the next time my transmission goes south this is something I will consider doing.



Stan

 

[soslow91]

Anyone who still has a stock converter and doesn't want to do everything involved in putting in a lockup tc in should consider a better non lockup tc the stock one is said to be about 69% efficient DTT sells an 89 and a 91 they are supposed to be the best but are also the most expensive I bought a Hughes but thanks to the hairbrained idea I got to rebuild a c4 transmission I haven't got it in yet.