trans shelled out... again

Would it be beneficial to drill holes in the direct drum for fluid evac? I have a TCS billet drum running 6 plates. Big blue I know you had a writeup on this somewhere but I can't find it.
 
12vCumminsFTW said:
Would it be beneficial to drill holes in the direct drum for fluid evac? I have a TCS billet drum running 6 plates. Big blue I know you had a writeup on this somewhere but I can't find it.
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If you want 3rd gear to engage firmer and have less total shift time, the evacuation mods did seem to help. I drilled a 1/4" hole at four locations lined up with the middle of the clutch pack on the machined reliefs for the steel plate lug engagement.

12vCumminsFTW said:
Huh, the guy that did the last rebuild put 15 springs in the direct piston. Faster release?


Sent from my iPhone 4s
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15 springs will release faster and apply slower because it will take more hydraulic pressure to overcome the spring tension. I usually just stick with 9 springs on the transmissions I build. If I was building a high powered 727 for a high RPM small block drag car, I'd definitely go with 15 springs.
 
Big Blue24 said:
If you want 3rd gear to engage firmer and have less total shift time, the evacuation mods did seem to help. I drilled a 1/4" hole at four locations lined up with the middle of the clutch pack on the machined reliefs for the steel plate lug engagement.

15 springs will release faster and apply slower because it will take more hydraulic pressure to overcome the spring tension. I usually just stick with 9 springs on the transmissions I build. If I was building a high powered 727 for a high RPM small block drag car, I'd definitely go with 15 springs.
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I'm switching to clutches with a lot more grooves in them then the last set , so that alone should help it engage faster. The drum already has the dual piston feed grooves so thats good.

I asked the guy who built my trans about the springs, he said with my drum/piston setup and 6 clutches he recommended 15 springs to help prevent bind-up. Basically slow down the apply a bit to let the band release. He also set the direct clearance at like .120. It seemed to shift ok so I'm gonna leave it.
 
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.120 seems like an aweful lot of clearance in direct. Ive been told you need about .010 per clutch and thats about what i go for in most clutch packs. .120 just seems like that piston would have to travel an awefull lot
 
Got the trans back in today. All seemed good running on jackstands, good pressure off idle, holding 180 psi line pressure, would drop like 15-20 psi going into lockup then ramp back up again to 180. After driving a bit and getting warmed it would run like 200 unlocked and drop to 175 locked, was holding power good. 1-3 shift good, OD is kinda soft.

Then on my way home the pressure started going nuts, it once spiked over 225 unlocked, then had really low pressure under 2500 rpm. Only 50 psi in gear at idle. Huge pressure drop in lockup. Tv lever is tied open and fluid looks good. Something wrong in the VB? BTW brand new converter, new seals in the trans ect, VB was taken apart and cleaned by a local trans rebuilder. When he cleaned out the VB he did say the pressure regulator was stuck, probably from all the crap in the fluid.
 
OK here is a crappy vid. The pressure kinda jumps around when shifting, and the huge drop in pressure was when I locked in 3rd.
[ame="http://www.youtube.com/watch?v=kh-sosY9YF0"]Trans pressure - YouTube[/ame]
 
What is the pressure reading at 4th gear unlocked WOT and 4th gear locked WOT at say 2000 rpm range?
 
Big Blue24 said:
What is the pressure reading at 4th gear unlocked WOT and 4th gear locked WOT at say 2000 rpm range?
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About the same as 3rd, maybe 120 locked, unlocked it shoots up to 150+. It will hit 200 psi unlocked, maybe 180 locked, but only if I run the rpms up over 2700. Wot doesn't make a difference as the tv lever is tied all the way back. Locking the converter under 2000 rpm drops pressure like crazy.


Sent from my iPhone 4s
 
OK, so I went out and started the truck and it was puking fluid out the dipstick tube. Shut it off, restarted it, stopped puking. Fluid was at the min mark so its not overfull. I let it warm up a bit and jacked up the rear end. Unlocked, pressure spiked to 240+ over 2500 RPM, locked 200. This was in any gear. Also pressure jumped all over the place when shifting. Something has to be up with the regulator? Not sure why it would puke fluid though.
 
well I was banned for not auto capitolizing .... SOOO I'm gonna beat it, dont need the grammer and spelling NAZZIE on my ass ... peace out
 
Well crap. I went out to move the truck today and it would just stall when I put it in gear like the TC was trying to apply. I pulled the pan and valve body and there is quite a bit of crap in the pan for less than 20 miles of running. Bunch of metal chunks in a VB port as well. Guess time to drop the trans again:bang
 
I'm starting to suspect the 5th forward clutch may have slipped off the hub and wore the teeth off. I'll know tomorrow when I pull the trans out. Whatever it was put metal flakes in the pan, hopefully its just some stuck valves in the VB causing the other issues.
 
Converter had to be pried off the trans, converter hub is ruined, scored and looks like it got hot. Pump bushing is reamed, tried to spin in the bore. Pump is destroyed. Metal shavings everywhere. The forward and direct clutch packs looked fine.

Any ideas on what would cause all this BS? I'm running a Suncoast flexplate, same one I ran on the last rebuild. Brand new converter. There was about 1/4" of play between the TC and flexplate so I don't think it was too tight.
 
Big Blue24 said:
It's possible you got a bad converter with too much run-out or a misaligned off-center hub.
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I'm starting to think that might be it, or the flexplate is warped. I will check the flexplate for wobble,and bolt the converter on the flexplate and check run-out on the converter snout.
 
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