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Uh-oh... 3-4 slip on upshift... what now?

MAXMSCL

MAXMSCL

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Phoenix, AZ
Had an ATS co-pilot installed about a month ago along with a deep pan and filled with Royal Purple Synthetic. Truck has a Juice w/attitude which has been on for over a year now. Usually only run it on level 3, wanted the co-pilot so I could play more. Have run it in 4,5 and 6 a few times with the co-pilot installed, always have made sure the co-pilot is set on the maximum setting when in the upper power levels. No problems till now...

Over the last few days I have noticed that it slips really bad when cold from 3-4, normal driving with co-pilot set on low setting. Gets a little better when warm, gets alot better when you turn up the co-pilot to mid/ mid-high setting. What have I done to my poor alli? Is it time for a re-build?

Any help is appreciated -
 
Are you sure its the trans slipping? Is the CEL illuminated? The reason i ask is because at one time my trans was doing a similar thing, turns out it wasn't the trans slipping. What happened was the fuel filter had gotten so restricted that at WOT it wouldn't shift, it would kinda hang in between gears and feel like it was slipping intsead of shifting. I changed my fuel filter and the problem went away.
 
Check your filters, both the fuel filter and transmission spin-on filter. If you've hurt the transmission it will set a code most of the time unless you lift the throttlr\e when you feel it slip.
 
Interesting guys, I will change it out and see if that helps. The fuel filter is fairly fresh, however I will admit it is a Fram.... (I usually use AC Delco but cheated with the Fram this time). No codes, no cel so that is a good thing. When I had the co-pilot installed they changed the spin-on filter at that time as well, just about a month ago.
 
yep check your filters. But if that doesnt work id say your in for a buildup.

You probably havent made the stock clutches happy with that copilot.
 
MAXMSCL said:
Interesting guys, I will change it out and see if that helps. The fuel filter is fairly fresh, however I will admit it is a Fram.... (I usually use AC Delco but cheated with the Fram this time). No codes, no cel so that is a good thing. When I had the co-pilot installed they changed the spin-on filter at that time as well, just about a month ago.
Click to expand...


used to run fram filters. they work ok on gassers but it seems that for as much fluid and at what pressures these diesels operate at, the frams dont do well. ac delco or oe is all i run now.... makes a difference.
 
6/1/08 - installed an AC Delco factory fuel filter, went for my test drive, seemed to shift ok set in the lower settings with the co-pilot, went ahead and turned the co-pilot off and it immediately started slipping :mad: Turned the co-pilot back on and set it on the middle setting and she shifts good with it set there.

One thing that I may not be aware of (based on the fact that I just dont know), is there a learning process when changing levels in the co-pilot? :noidea:

Any of you fellow co-pilot'ers familiar with this?
 
Im not sure if there is a learning process but it sounds like your problem is burnt clutches.

If it slips stock but not with the co-pilot theres a good chance youve burnt them up,

The reason they hold with the co-pilot on is because of the increased pressure of the copilot.
 
Yes, The Co-pilot helps the transmission shift quicker so the TCM see it and makes it's adjustment based on what it see's. I would turn the co-pilot off and start by making several 1/4 throttle runs up through the gears. If it shifts OK at that level then move to 1/2 throttle. Repeat the process until it shifts good then move on to 3/4 and full throttle. Make sure when doing this the transmission heat doesn't get hot. If the shift will not come around then it looks like transmission time is coming to you. This needs to be done any time you change the power setting on your truck.
 
Thanks for the test Diesel Tech! I have not been on here in a while and just now ready your reply. I will try tonight and report back with findings.
 
Well I have been driving with the co-pilot off for a few days now and performing Diesel Tech's test, have gotten it to shift solid up to around 40% but anything higher than that it will slip. Will continue testing throughout this week, if I cant get it to improve anymore than it will be tranny time :mad:
 
i ran the same setup on my dmax and had the same problem what you are experiencing is called a flare shift... come to find out there was nothing wrong with the tranny it was just the edge module doing crazy things... i went to an efi tune it my truck never ran or shifted so smooth. does it ever go dead when you pull up to a redlight
 
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