9 second wall and advice to help bust through............

Thank you for the replies and thank you Jeff for posting this for me. The truck/trans in question belongs to me. ill go through the trans history from the beginning best I can.

I hit the track last year and ran a best of 10.1 @132.91. Trans has what I consider best of everything as far as drums, shafts and clutches.

I made about 15 passes last year with small changes to fuel, timing and shift points trying to get it dialed in. my transmission issues last year were hard part failures , stripped internal clutch teeth on the direct clutches and it killed the hub but no burnt clutches, after I replaced the hub and direct clutches I stripped the splines out of the new hub with my input shaft ( truck shifted to second the same time my converter locked) last problem was my front shaft carden joint decided to let go after my launch so I didn't complete my run. each time trans was apart the problem was obvious and no plugged filter. that ended my year.


This year I hit the track with no changes over the winter and first time out I didn't have lockup. pulled trans and found plugged filter and clutch debris. forward clutches were perfect, band perfect, direct were perfect and overdrive were perfect.(I re used everything) I sent the converter out and I was sent a different one to get me racing by the following Friday (kick ass customer service) I made the event got 3 passes and lost line pressure ran around the 10.2 mark. I figured I smoked another converter so I pulled the unit again contacted phill and said I ruined more of your work can you get me out a replacement.... clutches were fine again no slipping or wear.


This time I figured a cross leak in the valvebody or stuck valve or something beyond my pay grade. took a virgin 47re valvebody I had and sent it off to be built so I could rule it out. this time I put it together fresh converter, new clutches and steels and valvebody. had 170 psi max line this time tv pinned around 70-75% had same problem after about 5 passes (pissed now) the trans shifted perfect lockup is solid and its not running hot the pan is cool after a pass and fluid is never burnt. type f


Pulled trans again and clutches were fine just a plugged filter. here we go again grrrr. This rebuild I changed the case all new seals, orings and second gear servo. I have a 48re stator support and my converter has a deep neck so I added the stator oring just because... now I have 190-200 psi tv at 70-75% 250 psi tv pinned and 330 in reverse. I hit the track again and make 3 passes and im loosing line pressure on the way back to the pits( down to around 100..... never missed a beat on the pass.


Ok what haven't I done yet???? fluid ahhhhha ill calm the sticky type f down and drain what I can and use dexIII maybe my forward clutches ( set up tight) are grinding/dragging while im in neutral waiting to race is causing the issue.... Hit the track again and made 2 passes and had good line pressure but when I got home I dropped the pan and had same issue, pictures above...

Im at a loss at this point, it was mentioned to call a reputable shop and ask what my problem may be, I can do that but the good guys are extremely busy and I hate chewing up someone's time with my problems on a trans they didn't build, hopefully one of them will jump on here and shed some light.. I think it may help quite a few at some point as your power increases...

A few side notes

I don't idle in neutral for 20 minutes while waiting to race more like 5.

Every time I dropped trans I flushed the cooler. its in the bed with a good working fan and never gets hot.

The converter is a 4 disk 2500 stall and the trips are 3 363sxe they light faster then a cigarette, I roll on throttle get 5psi bump in roll to 10psi 2ng light roll harder and boost rises as the light drops. never feels like I'm blowing through the converter at the line. I lock at 14mph.


Thanks for looking / helping guys, im at a loss. I cant post videos but Jason and Jeff have a video of my last run, maybe they can post it for me...
 
T-MAN said:
Thank you for the replies and thank you Jeff for posting this for me. The truck/trans in question belongs to me. ill go through the trans history from the beginning best I can.

I hit the track last year and ran a best of 10.1 @132.91. Trans has what I consider best of everything as far as drums, shafts and clutches.

I made about 15 passes last year with small changes to fuel, timing and shift points trying to get it dialed in. my transmission issues last year were hard part failures , stripped internal clutch teeth on the direct clutches and it killed the hub but no burnt clutches, after I replaced the hub and direct clutches I stripped the splines out of the new hub with my input shaft ( truck shifted to second the same time my converter locked) last problem was my front shaft carden joint decided to let go after my launch so I didn't complete my run. each time trans was apart the problem was obvious and no plugged filter. that ended my year.


This year I hit the track with no changes over the winter and first time out I didn't have lockup. pulled trans and found plugged filter and clutch debris. forward clutches were perfect, band perfect, direct were perfect and overdrive were perfect.(I re used everything) I sent the converter out and I was sent a different one to get me racing by the following Friday (kick ass customer service) I made the event got 3 passes and lost line pressure ran around the 10.2 mark. I figured I smoked another converter so I pulled the unit again contacted phill and said I ruined more of your work can you get me out a replacement.... clutches were fine again no slipping or wear.


This time I figured a cross leak in the valvebody or stuck valve or something beyond my pay grade. took a virgin 47re valvebody I had and sent it off to be built so I could rule it out. this time I put it together fresh converter, new clutches and steels and valvebody. had 170 psi max line this time tv pinned around 70-75% had same problem after about 5 passes (pissed now) the trans shifted perfect lockup is solid and its not running hot the pan is cool after a pass and fluid is never burnt. type f


Pulled trans again and clutches were fine just a plugged filter. here we go again grrrr. This rebuild I changed the case all new seals, orings and second gear servo. I have a 48re stator support and my converter has a deep neck so I added the stator oring just because... now I have 190-200 psi tv at 70-75% 250 psi tv pinned and 330 in reverse. I hit the track again and make 3 passes and im loosing line pressure on the way back to the pits( down to around 100..... never missed a beat on the pass.


Ok what haven't I done yet???? fluid ahhhhha ill calm the sticky type f down and drain what I can and use dexIII maybe my forward clutches ( set up tight) are grinding/dragging while im in neutral waiting to race is causing the issue.... Hit the track again and made 2 passes and had good line pressure but when I got home I dropped the pan and had same issue, pictures above...

Im at a loss at this point, it was mentioned to call a reputable shop and ask what my problem may be, I can do that but the good guys are extremely busy and I hate chewing up someone's time with my problems on a trans they didn't build, hopefully one of them will jump on here and shed some light.. I think it may help quite a few at some point as your power increases...

A few side notes

I don't idle in neutral for 20 minutes while waiting to race more like 5.

Every time I dropped trans I flushed the cooler. its in the bed with a good working fan and never gets hot.

The converter is a 4 disk 2500 stall and the trips are 3 363sxe they light faster then a cigarette, I roll on throttle get 5psi bump in roll to 10psi 2ng light roll harder and boost rises as the light drops. never feels like I'm blowing through the converter at the line. I lock at 14mph.


Thanks for looking / helping guys, im at a loss. I cant post videos but Jason and Jeff have a video of my last run, maybe they can post it for me...
Click to expand...

:fish:
 
That's a tough one because im kinda hanging on at the launch would a window of 3000 to 4000 be close? I launch manual first and shift to third after I know im going in a straight line. can you put up the video? you can see each shift from my rear suspension...

lockup was set at 40mph after the input failure ( 35 previous) and at the beginning of this year. I changed to locking at 14 after the new valvebody but I made a few passes with the new valvebody set at 40 then went to 14. feels better at 14
 
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That’s what those guys are there for, helping you get down the track. Calling multiple shops would give you a good sample of what’s going on in the industry to make these transmissions and converters live in a pickup going into the 8’s.

At this point it sounds like the problem is narrowed down to the converter.

I’m partial, but the boys at PDD have a wealth of knowledge on the 47/48re platform and getting it to perform well and survive a crap ton of abuse. Give them a call and talk to Will or Dustin about your problem. I think you’ll come away with a good solution to your problem. I can’t talk directly about your problem since I only really had a short conversation about converters being killed while staging, just give them a call. They’ll get you headed in the right direction.


Sent from my iPhone using Tapatalk
 
Mark Nixon said:
Personally, I'd talk to Phil Taylor.
I feel he communicates with people the best.

Mark.
Click to expand...

I spoke to phil on the original problem. He sent me a replacement before he cut mine open. His reply after cutting mine open was not a converter issue thought maybe a valvebody issue and he's not a valvebody guy. I respected his opinion and sent a different valvebody out to be built by someone with a test stand for the valvebodys. im still having the same issue. different valvebody, different case, different converter and all new steels, clutches, seals, bushings and intermediate servo. only thing I haven't changed is the builder... ive been building these things since 2000 but I am human and can make mistakes. I also never built one for a 1000hp drag truck. my hopes are someone has run into this problem before.... I wonder how many filters I can go through before I find the root cause of the problem....

I also want to say I'm not pointing a finger at phil, there's no way 3 of his converters could fail that quick.. I have an underlying problem I need to find. phil is always 100mph on the phone but always comes through when you need to hit the track.. I wish every diesel performance shop could do that....
 
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Sorry I tried to cover everything. the first converter was failed with welded clutches. was told not a converter issue to look at the valvebody.. when he sent the replacement out he hardly charged me anything to get me going again.. phil is a great guy.

Trans temp never get hot. pan temp never reaches 140* and I have a sensor that comes on at 165 in the hot side of the cooler and the fan has never come on. the last few visits to the track I keep the fan on the whole run. pan is cool to the touch with or without the fan on. type f or dex III never discolored or burnt smelling.


Since the only clutch I cant check is the converter clutches and the rest are fine im betting its converter clutch. but im getting a good lockup and no chatter...


I heard rumor of the top guys run about 9 passes then trans get rebuilt and converter get a refresh. im nowhere near there power so im still fishing..
 
I've seen the pan/filter pic, the fluid I see looks clean.
As I gather, the only thing failing is the converter clutch/linings and it shifts/locks hard and it does it without fail, right up the the point the filter plugs?
Is that correct?

Forgive me, but I am not an auto transmission expert, yet at first I was concerned about the filter's not being up to the task of moving high volumes of fluid, which I see is not the issue.

Mark.
 
Mark Nixon said:
I've seen the pan/filter pic, the fluid I see looks clean.
As I gather, the only thing failing is the converter clutch/linings and it shifts/locks hard and it does it without fail, right up the the point the filter plugs?
Is that correct?

Forgive me, but I am not an auto transmission expert, yet at first I was concerned about the filter's not being up to the task of moving high volumes of fluid, which I see is not the issue.

Mark.
Click to expand...

That is 100% correct
 
So, you've checked the cooler(s) for flow, all fittings and lines for obstructions?
You've ruled out everything that could remotely cause the issue, plus everything that's been mentioned in this thread?

Mark.
 
Yes sir, over and over and over. I even built two test blocks out of aluminum to check for leaks after assembly. none of it makes sense... I even made sure the little disk that is in 90% of the fat input shaft base from when they drill them out was removed....this is wearing on me …….
 
If you run the 48re stator seal, converter pressure will closely follow line pressure and 200+ psi will balloon the converter which can wipe out the pump, crank thrust bearings, or cause other general mayhem in both the converter function and other portions of the transmission itself. Simple fix, remove the 48re stator seal when running 200+ psi. Without the seal you'll have a little less line pressure but the converter will be much happier.

The torque converter switch valve serves a dual purpose as a torque converter pressure regulator when not in lockup. When you stage the truck and have over 150 psi line pressure, the converter pressure usually exceeds the regulation target psi and the regulation function starts to kick in.... unfortunately this causes the lockup clutches to drag. There are a few "proprietary fixes" that have been developed to prevent this problem. I won't go into detail on an open forum, for respect to the craft of building high HP diesel race transmissions but if you call-in, we'd be more than happy to help you privately understand what needs to happen with your valve body to fix the problem. The dragging lockup clutches are most likely making the debris plugging your filter.

Third, with a mechanical injection Cummins engine with fixed timing, you generally need much higher stall speed to get big chargers lit than an electronically controlled variable timing engine. This means you're going to be using stall speeds not commonly used for a Common Rail so you might not get the correct help if your tranny VB Builder has little to no experience with high rpm stall speed setups and the myriad of weird tranny issues that come up with these setups. We've found that even if the regulation function of the converter lockup switch valve is defeated or altered, once staging RPM exceeds 2800, a "proprietary" converter dump valve is necessary to keep the lockup clutches from dragging. Basically, to hold a big nasty launch on a race truck, you typically need more than 150 psi line pressure to keep the tranny from slipping at the the starting line when stalled up against the converter. When the converter is fed higher line pressure, at 2800+ RPM, the lockup clutches start dragging. Some builders are focusing on regulating the converter feed, others are simply telling their customers to get a lower stall and spray it to light the chargers. We came up with a trick dump valve setup... We literally spent hundreds of hours on this problem and burned up several converters in the process before we developed a reliable fix. We went as far as putting a transbrake in the Junker so we could test 60+ psi boosted launches (way more than the rear brakes could hold without transbrake assistance) to replicate the forces we were seeing with the triple GTX55 charger 6.8L UCC engine setup.

One final bit of advice, once you get your trans working properly, you will probably pick up some trap speed/power to the track. However, if you're not trapping 138MPH or so after the trans fix, you're still a little short of a reliable 9 second setup. No sense killing it every launch and hurting parts if it continues to see sub 138 MPH trap speed. Obviously most of your time is made up the first part of the track so suspension mods that produce reliable and repeatable 60' and 330' times will be key for reliable 9 second times and reliability in the transmission hard parts. My truck only runs 10.50's and 60's at 134 to 135 MPH, but rather than kill it chasing 10.2's or 3's, I'm spending time upgrading the suspension and power so I can easily get into the 9's without bouncing from wicked hard glory pass launches that may or may not hook. I knew my suspension was not ready for "big power" so focusing on getting reliable tune-able suspension now!
 
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