Replacement Torque Converter: driveability & longevity vs stall speed

[PawsWet]

I just joined the club of Dodge owners with a failed TC stator sprag. Like many posts I've read, mine started not long after a transmission service. Bought the truck in Jan with 90k miles. Had transmission serviced with a flush, filter change, and band adjustment. Less than 1500 miles later, the sprag clutch failed, suddenly. Slowing below 5 MPH became difficult, and both engine idle and turbo speed would increase approaching a stop. I never waited to see what would happen..it felt wrong, so I just shifted to Neutral. Other than a TC drainback change, there was no abnormal behavior prior to this failure. In fact, (stock) shifts had been noticeably better since the service. When cold, it seemed to prefer a 10-15 sec delay after start in neutral prior to selecting drive. I did not notice this drainback issue before the service. Maybe the check valve was fouled, who knows?

Back to to the point- I am leaning towards a Goerend GT TRPL TC 4748RE 3 disk billet cover model to replace the poorly designed stock TC. My question involves driving characteristics of the 15SS (200-400 r/m lower stall) vs 17SS "stock stall" options.

I haul kids, commute, and occasionally tow moderate weight trailers long distances (boats, bovines, etc). Your opinions are requested for my stall speed choice. I haven't added power yet. If I tune, it would be for towing and/or mileage. Will mileage be noticeably affected by stock stall vs lower stall? Any thoughts on driveability with these two options? Longevity?

Input appreciated. I've read only positive things about this manufacturer. Any input along those lines should perhaps be a PM, considering the new guidance.

Thanks!

 

[Bob4x4]

I have to ask where you got the flush performed.The failures after a flush can usually be attributed to the use of a flushing chemical that is used not the flush itself.

 

[PawsWet]

It was a nearby Dodge dealer. Lead transmission Tech is well known in the area. In contrast, the transmission specialty shops around here have been notorious for shadiness--for decades. My understanding was that the flush was with ATF-4+.

 

[BigPapa]

I can't speak to the stall, but I'll tell you, you can't go wrong with Goerend's. I love mine. Call and ask Dave about the stall. He knows his product and he'll shoot you straight.

 

[Bob4x4]

It was a nearby Dodge dealer. Lead transmission Tech is well known in the area. In contrast, the transmission specialty shops around here have been notorious for shadiness--for decades. My understanding was that the flush was with ATF-4+.

Most trans flush machines are owned by chemical companies to push their products(exorbitant priced)FCA does not have any trans flush machines

 

[WalterJ]

I had similar questions 4 years ago when OEM transmission was rebuilt. With my Montana hooked up, my 716rpm idle gets us moving soon as brake is released, even on a slight grade. My shop ordered a 'custom' lower stall spec from Precision for my triple disc. I'll call them tomorrow for actual spec.

If it's allowed, here's a nice writeup to begin explanation; http://bankspower.com/techarticles/show/10-Understanding-Stall-Speed

 

[promisedland]

Talk with Dave, ask for him and talk to him. The ladie at the desk advised a 15'SS' TC but when i talked to Dave he said the 900/400 would prob suit me better, lower stall. I have some extra power, not crazy, but i love the lower stall! No check eng lights at all.
If your keeping your power moderate; I would go with the single disc TC, not triple disc, with a shift kit.[this raises trans pressure], I have the triple disc and shift kit and if im TC locked in 3rd and trans shifts to 4th, my TC cant unlock fast enough so i end up with a locked shift. I expect a single disc would help here.

 

[PawsWet]

If your keeping your power moderate; I would go with the single disc TC, not triple disc, with a shift kit.[this raises trans pressure], I have the triple disc and shift kit and if im TC locked in 3rd and trans shifts to 4th, my TC cant unlock fast enough so i end up with a locked shift. I expect a single disc would help here.

Matthew, this is exactly what I was looking for. Thank you!

While I would like the added holding friction of a triple disk, if that means locked shifts or doing metal fatigue research, it becomes a deal breaker for me. I don't see the need to go above 800 ft*lbf torque, and I'm still stock.

Goerend's website doesn't mention anything about single disk products, and I can't get a call back from them. Who makes a high quality single disk converter?

 

[p-Bar]

If your putting in a triple disk put a valvebody in too. Goerend products are excellent

 

[BigPapa]

Goerend's website doesn't mention anything about single disk products, and I can't get a call back from them. Who makes a high quality single disk converter?

Enhance your calm. Your dealing with a relatively small company that does a LOT of business and you're wanting to talk to "The Man". It may not happen in a day. Be patient. Don't jump to another supplier just because you didn't get a call back in an afternoon.

 

[SnoKing]

Lower stall speed TCers do not make for a very good off road experience(I had a DTT 89%). In low range the motor/drive train will over power the rear brakes. I went down the Shafer Hill at Moab and had to keep going into neutral on the switch backs. In two low the truck was very jumpy trying to spot the 5th wheel in a camp site. Also created a lot of ATF heat in stop and go traffic. SNOKING

#ad

 

[PawsWet]

Thanks SNOKING! Backing trailers accurately and slow off road ops are part of my routine. Sadly, so is stop and go traffic in Texas heat. Sounds like stock stall is pulling ahead in the race for my application. Nice picture!

BigPapa, point taken. It's hard to be patient when the truck is in the shop and I have to use Uber to get to work. I'll try harder

 

[AEdelheit]

I just had my transmission done by a small shop that uses Gorend parts with a 15SS converter, full valve body and a few other goodies. The shifts are great, the TC does not lock to hard or unlock to slow, quicker to get the truck moving but still easy to keep stopped with light brake pressure. I have no issues with a triple disk converter when its set up right, but if someone mixes a bunch of parts together and uses the wrong converter I have seen them be very harsh and unpleasant to drive, no a problem you need to worry about with Gorend. Heat can be an issue with a tighter converter but that is just part of driving an automatic and can be addressed by another cooler, one of the nice things about a Gorend VB is you can have cooling in park where you do not stock.

 

[BigPapa]

Paws, Dave's right hand man is also good. I can't remember his name, it's been a few years since
I called them.

Also, I will agree with the posts above about the valve body. Dave's TC are a great piece, but his magic is in the valve body.

 

[Bob4x4]

I have a billet cover single disk t/c(my trailers are not too heavy) and it works awesome offroad.It does not creep or push at idle,it does an amazing job in all off road conditions from rock crawling to desert racing to flying through sand bowls and hill climbs.It hooks earlier than stock but not too low.There is some art to specing set ups

 

[cerberusiam]

A Goerend 900\400 single disk billet cover TC and a shift kit will make you ask the question: Why did I wait so long?


A lower stall tighter TC will actually reduce observed temps in most conditions and enhance and EBB efficacy. The engine has so much TQ that is better put to use with a good TC it makes a huge difference in drivability. The sprag failures are just a fact of life with a cheap stock TC and a high TQ engine, been that way for years. Doubtful a flush was done anyway as these tricks cannot be successfully flushed, probably just a fluid exchange. No correlation to fluid exchanges or anything except time and wear.

 

[promisedland]

Pay attention paws, ^^^

 

[Prairie Dog]

Lower stall speed TCers do not make for a very good off road experience(I had a DTT 89%). In low range the motor/drive train will over power the rear brakes. I went down the Shafer Hill at Moab and had to keep going into neutral on the switch backs. In two low the truck was very jumpy trying to spot the 5th wheel in a camp site. Also created a lot of ATF heat in stop and go traffic. SNOKING

#ad

So do you think it;s a problem (besides the heat) for a truck equipped with the 89% or higher wanting to pull the truck ahead in stop and go traffic or was it just compounded by being in low range?
(asking for a friend)

Thx
Scott

 

[SnoKing]

So do you think it;s a problem (besides the heat) for a truck equipped with the 89% or higher wanting to pull the truck ahead in stop and go traffic or was it just compounded by being in low range?
(asking for a friend)

Thx
Scott

I measured transmission temps at the output line. In stop and go freeway stoppages I would see transmission oil temps what to climb beyond 240 degrees in 10 or 20 minutes of stop and go, and would have to put transmission in neutral when stopped. The DTT 89% with low stall speed required quite a bit of brake application to hold get back when it gear. Normal driving give the truck a very tight connection between the go peddle and performance. It was fun to drive with around 325/650 at the rear wheels. I listed the down sides earlier. SNOKING

 

[cerberusiam]

An 89% TC is REALLY tight and that is a downside of them, not a good all around TC. Even Bill K. admitted that was probably not the best TC in a multi-use scenario. He always recommended something more like an 85-87% by his estimation for better drivability.

There a different ways to achieve a tighter TC, not all are going to cause that much heat or pull thru the brakes. However, it doesn't matter if you are loaded in hot weather going stop light to stop light trans will bounce off of 240 with enough power in front of it. Just the physics of it.

Goerends TC's have more than a little patented engineering in them to enhance the operation, unlike a lot of manufacturers that just tighten things a little then put a triple clutch in them to hold. The 900\400 and 15 blade left cut seems to be a really solid unit that performs well in a variety of scenarios. I am considering his 800\300 version for mine but need to explore things a bit more with Dave.