AGRV8D, frustrated, almost calling it quits

[RedHeartbeat]

Okay, explain a little bit more details here. You're having problems with the transmission not shifting? What transmission are you running? Do you have a 93 4L60e or the 4L60e the came with the LS1 engine?

[93Ext5.7ltr]

Hi RedHeartbeat,

I am having problems with the tranny not shifting.....but they are periodic and literally differ each time I start up the engine...sometimes it works fine, sometimes it won't downshift (the problem I'm trying to work out).

Actually neither.... 1993 tranny won't work with a 1999 LS1 computer setup. There were changes made to the way the tranny talks to the computer (about as much as I understand), so you can't make my original tranny work with the setup (and keep it electronic/computer controlled).

What I have is a built 4L60E - maybe someone could give me pointers on where the serial number is on these and I'll post it.

Anyway, for what its worth, just "ran" to the grocery store and played with a stock 02' Mustang GT - dispatched easily.

I then met up with a older modded foxbody - guess mid - late 80s? Anyway, he hung with me about like the SRT-4 I raced a while back (about a length to a length and a half back) and we definitely pushed this one up - well over a 1/4 mile. Had he not turned off, I'd have asked him what his 1/4mile time was.....he he

Still confused about this.....

[RedHeartbeat]

The program in the PCM controls upshifts taking into consideration the throttle position percentage. If you consistantly accelerate at about a 30% or greater TPS load it should upshift religiously. If your internal shift solenoids do not have the built in filters you should replace them just for safe measures. I had to do that on my trans when I rebuilt it. You could also have defective downshift solenoids.

Does your trans shift 1-2 fine but when you expect 2-3 shift it free revs like you stuck it in neutral? Do you have a stall converter greater that 3200 rpm? If so, you'll have to disable a couple PCM codes to keep this free-wheeling from happening. I drove mine like that long enough I eventually destroyed the transmission. Does your transmission have a vacuum operated fluid pressure device on it and if so, does it have a good vacuum source to it?

[93Ext5.7ltr]

<div class='quotetop'>QUOTE(RedHeartbeat &#064; Mar 29 2006, 11&#58;05 PM) [snapback]48708[/snapback]</div>

The program in the PCM controls upshifts taking into consideration the throttle position percentage. If you consistantly accelerate at about a 30% or greater TPS load it should upshift religiously. If your internal shift solenoids do not have the built in filters you should replace them just for safe measures. I had to do that on my trans when I rebuilt it. You could also have defective downshift solenoids.

Does your trans shift 1-2 fine but when you expect 2-3 shift it free revs like you stuck it in neutral? Do you have a stall converter greater that 3200 rpm? If so, you&#39;ll have to disable a couple PCM codes to keep this free-wheeling from happening. I drove mine like that long enough I eventually destroyed the transmission. Does your transmission have a vacuum operated fluid pressure device on it and if so, does it have a good vacuum source to it?
[/b]

Thanks for the info. The truck shifts fine in normal driving conditions 1, 2, 3, OD, R, P, N. It just doesn&#39;t want to downshift when at part throttle and then you mash it. The stall is somewhere between 21 - 2300rpm. Not sure about the downshift solenoids, but this could be part of it I guess. I don&#39;t know if the tranny has a vacuum operated fluid pressure device. How can I check/confirm?

Thanks for the help man&#33;

[RedHeartbeat]

Just look for a vacuum line running to the transmission from the engine. I can&#39;t remember which side of the transmission the vacuum line runs to. A lot of performance transmission builders use the Transgo vacuum modulator on the 60E&#39;s for consistant fluid pressure control.

Check your throttle position sensor connector for good contact and functionality since it helps to trigger your downshifts.

[93Ext5.7ltr]

Wrote a message to Tony Mamo @ Air Flow Research (maker of AFR heads). He replied with the following, which didn&#39;t make me feel better, but gave some insight into why I&#39;m seeing the smallish gains:

"Shorty headers are useless and the big question is why didnt you baseline the combo....That trans will sap lots of rearwheel power as well....especially with a converter....are those locked or unlocked numbers??

I think the results are in line all things considered....A vette with a baby cam and an A4 with shorty&#39;s would be lucky to crack 400 RWHP. I bet your driveline is sucking 140 HP from the power eqaution...LOL

You get the picture....

Good luck...keep me posted

Tony
__________________
Tony "Morpheus" Mamo invites you to take the Blue Pill...welcome to the "real world" "

[ULuze2]

I had the same problem, wound up being 1-2 shift silinoid and force motor being turned up to much

[93Ext5.7ltr]

<div class='quotetop'>QUOTE(ULuze2 &#064; Apr 7 2006, 07&#58;41 PM) [snapback]49587[/snapback]</div>

I had the same problem, wound up being 1-2 shift silinoid and force motor being turned up to much
[/b]

Hi - got the 1-2 shift solenoid thing - but what is this about?

"force motor being turned up to much"

Thanks.

[ULuze2]

when i had the shift kit put in he turned up the line pressure by turning the force motor up which caused a problem making my truck short shift and not down down shift because the computer saw like 190psi in reverse and like 90-120psi in any foward gear