[rcoe]

here is the best log to show it. Going down my driveway shifts fine at part throttle. Then I reverse back and when I try to go forward again it is like it is in neutral. Going from neutral to drive did not change idle rpm at all like I never shifted from neutral.

[cjperformance]

Log shows lots of trans slip in first gear :( I mean... to me... this seems like either another electrical gremlin of some kind, or a fluid issue. But seeing how its acting... I'm thinking more along the lines of electrical gremlin now.

I would think if the clutches were so burned out they would freewheel, it wouldn't be shifting normally for the first half, then freewheeling after a few minutes. And the fluid issue I proposed... dunno... I suppose it could be that, but not sure. I recently read a story or saw on youtube or something that someone left the plastic wrapper on their new trans filter and under suction it would cut off the fluid... I dont know how likely that is for your situation.

I don't know what part the TCM plays in this too... meaning where the selected gear value in HPT comes from. Could it be a communication issue between ECU and TCM or something? Just shots in the dark. Sorry, prob cant help much more, but would start looking at either electrical issues and/or drop the pan.. Or even better, consult someone more knowledgeble than me !!!

[rcoe]

Originally Posted by cjperformance

Log shows lots of trans slip in first gear :( I mean... to me... this seems like either another electrical gremlin of some kind, or a fluid issue. But seeing how its acting... I'm thinking more along the lines of electrical gremlin now.

I would think if the clutches were so burned out they would freewheel, it wouldn't be shifting normally for the first half, then freewheeling after a few minutes. And the fluid issue I proposed... dunno... I suppose it could be that, but not sure. I recently read a story or saw on youtube or something that someone left the plastic wrapper on their new trans filter and under suction it would cut off the fluid... I dont know how likely that is for your situation.

I don't know what part the TCM plays in this too... meaning where the selected gear value in HPT comes from. Could it be a communication issue between ECU and TCM or something? Just shots in the dark. Sorry, prob cant help much more, but would start looking at either electrical issues and/or drop the pan.. Or even better, consult someone more knowledgeble than me !!!

This is what I am thinking now too. If the plates in the TC or inside the trans itself were burned I think the problem would always be there and the fluid while dirty was not burned. Something whether it be electrical or hydraulic is telling it to shut down and I would think if it was a stuck solenoid inside I would be getting codes.

Either way I am going to drop the pan this week and replace the fluid and filter, just need to get the fitting to refill it.

[rcoe]

After reading all day and starting to really think it was something electrical.

Got home did a couple very short pulls and now am thinking something is toasted inside.

Looking at this graph can see all the slipping only moved maybe 20 feet the whole time and never went above about 5mph and was stopped for the last few seconds.



And here is a longer one where I did get thru the gears a little but was definitely stopped when I cut the log.




Here is the full log of the longer one.

Once it gets warmer I have less time before it stops.

[rcoe]

Well braved the heat tonight sucked as much fluid as I could out then dropped the pan. Fluid was dark and dirty but did not smell burned in any way.

Took the filter off, cut it open and the element was very dark but no real signs of debris or any metal, magnets had some sludge on them but no metal. Everything I could see looked good and the pump chain was good. This trans should only have around 12k(car only has 17k on it) on it since the converter was installed and the fluid should not look this bad.

Cleaned it all up and pumped 6 qts of fluid in, but needed a little more. Going to pickup 6 more tomorrow, overfill and try to flush some more of the dirty stuff out. Then see if it makes any difference.

[laynlo15]

Mine is usually around 30 to 32 mph on the back half.
9.80@142.96 1.44 60ft, 6.34@112, here is another pass 9.86@142.13, 6.38@111.12

[rcoe]

Originally Posted by laynlo15

Mine is usually around 30 to 32 mph on the back half.
9.80@142.96 1.44 60ft, 6.34@112, here is another pass 9.86@142.13, 6.38@111.12

But does the A10 have more favorable gearing for that final shift. In 4th it was pulling very hard then it hit 5th and it was a bit flat for the first bit and did not really get back into the power band until just before I crossed the line, maybe need to push the 4-5 shift point out just a bit.

As for the trans filled it up the rest of the way and it drives good, did and 80% pull from 2nd and it shifted great all the way up to 120. Even if it keep running good do not know if I will be able to trust it, so will most likely end up pulling it later this fall and building it up and having circle D check the converter.

[laynlo15]

Originally Posted by rcoe

But does the A10 have more favorable gearing for that final shift. In 4th it was pulling very hard then it hit 5th and it was a bit flat for the first bit and did not really get back into the power band until just before I crossed the line, maybe need to push the 4-5 shift point out just a bit.

As for the trans filled it up the rest of the way and it drives good, did and 80% pull from 2nd and it shifted great all the way up to 120. Even if it keep running good do not know if I will be able to trust it, so will most likely end up pulling it later this fall and building it up and having circle D check the converter.

I trust it like my A8, we don't push the trans as far as removing torq management, that's when it start slipping, people get greedy to pick up a 1/10 or more. We just removed enough to keep GM from pulling timing on the launch. Picked up some, we could gain some more et if we just built a drag tune only, we didn't do that yet. I run a little bit less agreesive trans tune for the street, don't want any slip at all as the trans gets so much hotter on the street than it does on one pass, gotta take all those things into consideration. My 16ss went 9.41@147, we never touched the trans on that A8 except for shift pressures, no TM removed at all and it made over 300 passes down the track and had never been out of the car, couple motors went down the road, it even had the stock converter in it all that time. I did dump the fluid from the converter between motors, it was a very reliable trans and converter.

[arpad_m]

Originally Posted by rcoe

But does the A10 have more favorable gearing for that final shift. In 4th it was pulling very hard then it hit 5th and it was a bit flat for the first bit and did not really get back into the power band until just before I crossed the line, maybe need to push the 4-5 shift point out just a bit.

As for the trans filled it up the rest of the way and it drives good, did and 80% pull from 2nd and it shifted great all the way up to 120. Even if it keep running good do not know if I will be able to trust it, so will most likely end up pulling it later this fall and building it up and having circle D check the converter.

Your only hope is to hold off on the 4-5 shift as long as you dare. The A10 has an extra gear between the A8's 4th and 5th, which helps a lot in this situation.

[laynlo15]

I go thru the traps in 6th gear at 6000 or so. I would be awesome to be able to keep it in 5th gear but we just don't want to push the motor to 6600 or 6700 to keep it there until we cross the line. We shift out of 1st at 6300 and the rest of the shifts are 6400 so we aren't hurting the motor or running too much boost. If was shifting at about 6500 or 6600 our boost level would be above where we want to run it. I guess for a bonzi really fast pass we could do that, I like the motor more than a 10th of a second. In the past on my 16ss I wouldn't have thought twice. This motor is staying together for as long as I own it.

[laynlo15]

I forgot to congratulate you on your 1st 10 second pass, hopefully many more . Next work on getting into the mid 10s then lower it when the weather gets really good this fall.

[rcoe]

Originally Posted by laynlo15

I forgot to congratulate you on your 1st 10 second pass, hopefully many more . Next work on getting into the mid 10s then lower it when the weather gets really good this fall.

Thanks not sure if I will get back this year, most of Sept. I am busy on the weekends, horse stuff with my daughter. October maybe but weather up here is starting to get iffy by then.

I just really need to figure out how to get a good launch, if I could pull even just a 1.5 60ft that should put me in the low 10's at 140. Maybe airing down the tires a bit more, I had 21 in them maybe down to around 17. It is also entirely possible this trans is slipping especially with the way the fluid looked.

[laynlo15]

What have you actually done to the trans?

[rcoe]

Originally Posted by laynlo15

What have you actually done to the trans?

At around 5k miles when the engine was built they installed a Circle D converter, do not know which one or if anything else was done to it. All work was performed by a local speed shop that has since went out of business. Assuming the rest of it is stock.

After swapping out the filter and cycling 12qts of fluid through it, now it is running good again. Assuming the thinker new fluid helped. Put a 100 or so mile on it the last couple days, everything feels good, but I do not trust it. So once it goes into storage this winter will pull it put all new plates and have the converter gone thru.