Another converter failure

[TYTILIDIE]

Well, last time I had my trans out I decided to send my TCS converter back to get the hub replaced. Out of curiosity, I wanted to re-install the converter that I bought locally to see how it would do. Well, it looks like it may have taken the trans out. I pulled it today and the entire converter looks like it was exposed to super high heat. The paint on it was discolored as was the lower half of the hub.
before

after


The pics don't show it much but trust me when I say that the thing looks like it sat in an oven for a while. I replaced the flexplate and it appears that front pump seal is again, worn on one side. I don't know what to do about this crap.

Plan right now is to tear down the trans and see if the converter destroyed anything which it smells like it did. Basically what happened was I went WOT up to 100 or so and the trans started to feel like it was slipping. I let off and made it home. The next day I drove it and it was defaulted to second. When I tried to hook up DM to see what the trans doing it would not connect and said there was no PCM. So I think maybe the PCM fried? A week before that I took a buddy of mine out for a ride. We went looking for some races and I pull up on a guy in a modded SRT4

I launched the truck and got a real nice launch. I got the pretty good but afterward we went from about a 45mph roll, at about 90 I started passing him. Not sure how fast I was going but I saw fluid all over the back glass. I was sure the front pump seal blew out again. The trans felt like it was slipping so we went and dropped it off. Next day I looked under there at the seal and not only was there no fluid on the ground, there was none anywhere on the outside of the trans either. So I don't know if its pushing passed the rubber or what but something is definitely ****ed about this whole thing.

I am at my wits end here. Should I just bite the weenie and take the whole damn thing to someone or should I give it one more go with a minor rebuild, new flexplate and totally different converter? Or should I just sell this POS!

 

[Beavis]

Re: Another converter failure

your luck with transmissions.......Is there anyone close to you that does racing trans? Try consulting with them or have them double check your work and double check roundness and straightness on everything. Good luck......

 

[Quickstop [UK]]

Re: Another converter failure

The heat and the trans locking up are probably from fluid not getting to where it needs to be and overheating. Maybe the converter is the cause but I don't know.

Sounds like something internal to me - valve body check ball or one of the valve body plates perhaps?

You might spend a tonne of time and money trying to diagnose it. What's your time worth to you/ how much do you want to know how to do a trans?



If you're ok with a minor rebuild and have the time, I personally would like to do that. Depends what your priority is.

I suspect you'll need to bite the bullet after that though.

Good luck mate!

 

[DaveP]

Re: Another converter failure

Stock 4L80e and the programming have what is called PWM'd TCC apply. The TCC is never completely locked, it is allowed to slip at the rate of about 3-8 RPM. The TCC solenoid controls this PWM in the 80e.

The TCC shift valve also regulates the flow of oil to the cooler outlet. Unlocked, the converter-out goes to the cooler. Locked, straight line pressure goes to the cooler. So the TCC solenoid state controls cooler flow.

2nd gear is commanded by OFF-OFF shift solenoids. No power to the trans will result in 2nd and R only.

Did you ever log your pressures at various TPS values to see if the commanded pressure was adequate? If line pressure was low, this will burn it up very quickly. Like your WOT to 100. There is NO "pressure feedback" loop in the 80e. Ie, it's not like an engine in Closed Loop where the o2 sensor reports back to the ECM, and if the mixture is not "what it wants" the eCM makes an adjustment. The Pressure Control System is commanded to a ceertain current, and the pressure is supposed to be "X" at that current. The program uses a map of TPS, RPM and Gear selected to command a desired pressure. If that pressure isn't actually achieved, the ECM will never know, and parts will fry.

When you get it running again, run a pressure gauge until you have confidence that Line Pressure is being correctly commanded and achieved.
Check your TCC control schedules, and transmission hardware to be sure it's set for non-PWM'd usage, and that cooler flow is adequate when un-locked.
The 2nd-only is un-related to the burn-up, IMO.
And how about a trans temp gauge? Or monitor the internal TTS in your PCS dashboard.

There's some food for thought.
DaveP

 

[Quickstop [UK]]

Re: Another converter failure

Did you go with a PCS unit or did you wire in a stock ECM? I was under the impression you could read line pressures from the PCS but if it's open loop as Dave says, that's probably not possible.

DTC codes would show up first - again, not sure how that translates with the ECM if not a PCS/TCI unit.

 

[midnightbluS10]

Re: Another converter failure

I thought he had 700's in his Tys :dunno:

 

[Quickstop [UK]]

Re: Another converter failure

Mike's install thread

 

[TYTILIDIE]

Re: Another converter failure

Thanks Dave, this is actually god advice, advice that I failed to take from myself from day one. No one to blame but me right there. I have disassembled the trans and it all seems to look pretty good. There is a LOT of metal in it though but it did not come from the clutches. Clutches look new still which makes me think the converter did indeed take a dump on me. Yesterday, I dropped off the input shaft and the front pump to a trans shop for inspection. I want to make sure nothing is bent (at the advise of FIVETODRIVE) and that it is all assembled right.

After talking to Ben yesterday for about 20 minutes (always been a real helpful guy to me) he kind of reamed my ass for driving a truck with a 3700 stall on the street like its nothing. He told me that will be my main problem in the end. For now I am shrugging that one off. In direct reference to my actual issues, he is recommending that I empty the case so I can manage it easily and mate it to the back of the engine to see if the dowels pilots are maybe too big are allowing the trans to be crooked. So that is on the agenda for today.

Once I figure out a real answer to the failure of these parts and I get the trans back in, you can count on it that I will not waste anymore time tuning my engine. I will hook up my trans gauge, install a temp gauge and tune the trans to what it really should be. I would really like this to be the last time I take this thing out for at least a year.

 

[JSM]

Re: Another converter failure

Once you build it up would it be worth finding a shop to put it on a trans dyno, they can check everything out there before you go through the effort to reinstall it.

 

[TYTILIDIE]

Re: Another converter failure

Yeah, if one exists around here. I'll have to call around. I doubt anyone close to here would have something like that though.

 

[DaveP]

Re: Another converter failure

If there's metal in the trans, throw your coolers away and install new ones. OR take the coolers to the trans shop and have them hook them up to their flushing machine and clean them for you.

There is NO way to get the metal out of the coolers without using one of these machines. Even then, you should install a cooler line magnetic filter in the return line to capture any remaining chunks. The cooler return flow goes straight to the lube circuit. So any remaining metal WILL go straight into bushings and bearings.

When they "make metal" it's a real mess to clean up.

 

[ranger]

Re: Another converter failure

Hey Quadrjet 72,

Where does one buy an in-line magnetic filter??

Thanks!

Best,

Ranger
Aiken, SC

 

[DaveP]

Re: Another converter failure

Where does one buy an in-line magnetic filter??

Google ownz. There's a gillion of them, but this is kind of what I had in mind.
http://www.summitracing.com/parts/WIX-58964/?rtype=10

 

[TYTILIDIE]

Re: Another converter failure

If there's metal in the trans, throw your coolers away and install new ones. OR take the coolers to the trans shop and have them hook them up to their flushing machine and clean them for you.

There is NO way to get the metal out of the coolers without using one of these machines. Even then, you should install a cooler line magnetic filter in the return line to capture any remaining chunks. The cooler return flow goes straight to the lube circuit. So any remaining metal WILL go straight into bushings and bearings.

When they "make metal" it's a real mess to clean up.

I always thought that was just if you use the radiator cooler? I have two coolers that are just round tubing the whole way, think I should still buy new ones? I would imagine they would flush just fine. Basically have two of these

 

[DaveP]

Re: Another converter failure

I always thought that was just if you use the radiator cooler? I have two coolers that are just round tubing the whole way, think I should still buy new ones? I would imagine they would flush just fine.

You be the guinea pig, then. Clean them yourself. Install one of the inline filters I suggest above. Run it a few thousand miles. Remove the filter, cut it open and inspect it for debris. Post up how you did.