4l80e trouble
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Having a little trouble with my new tranny, it worked good for about a month or so but now it is acting strange. Whenever it sits for a day or more it is like it is low on oil and will barely move. After a few secs it starts to move and after about 5 secs it is good and continues to be normal, as long as it doesn't sit for more than a day, then it will do it again. Any ideas of what could cause this? Is there some sort of valve that keeps the oil up in the tranny or something? - i've never been real deep into an automatic tranny before.
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There is a bulletin out about it saying its normal due to torque converter bleed off. Its probably set a p1810 also. It tells you to idle it for awhile before putting it in gear.
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It does sound like converter bleed down , You will find that if you place the trans in neutral for a few seconds after start up or idle just a little longer in Park it should not have the issue, The bleed down can be from several causes ranging from the converter to stator bushings etc. I wot say its a common issue but I have heard of it in the 80e and its actually very common in the 518 dodge trans the full time lube mod to the PR valve fixes it there however.
But that is what it sounds like
But that is what it sounds like
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#PIP3857: Harsh Shift After Cold Start - keywords DTC MIL P1810 - (Jul 11, 2006)
Subject: Harsh Shift After Cold Start
Models: 1998-2007 Light Duty Trucks and Vans
Equipped with a 4L80E/4L85E Transmission
--------------------------------------------------------------------------------
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
A 4L80E may intermittently set DTC P1810 and exhibit harsh shifts. Freeze frame/ fail records may show the vehicle was in reverse and the P1810 set shortly after a cold start. The vehicle may also have not been started for an extended period of time.
Recommendation/Instructions:
This condition may be inadvertently induced by starting the vehicle and immediately shifting the transmission into a drive range or reverse. If the PCM does not see a PRND43 input from the transmission fluid pressure switch before the customer shifts into a drive range or reverse, the PCM will assume the TFP is malfunctioning because the PCM did receive a signal from the PRND43 switch and set the code P1810. This condition would occur more easily if the vehicle has not been started for an extended period of time because of torque converter drain back. DTC P1810 does not turn on the MIL the first failure, but does store the code and it commands maximum line pressure. The customer will probably notice only the harsh shift.
Subject: Harsh Shift After Cold Start
Models: 1998-2007 Light Duty Trucks and Vans
Equipped with a 4L80E/4L85E Transmission
--------------------------------------------------------------------------------
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
A 4L80E may intermittently set DTC P1810 and exhibit harsh shifts. Freeze frame/ fail records may show the vehicle was in reverse and the P1810 set shortly after a cold start. The vehicle may also have not been started for an extended period of time.
Recommendation/Instructions:
This condition may be inadvertently induced by starting the vehicle and immediately shifting the transmission into a drive range or reverse. If the PCM does not see a PRND43 input from the transmission fluid pressure switch before the customer shifts into a drive range or reverse, the PCM will assume the TFP is malfunctioning because the PCM did receive a signal from the PRND43 switch and set the code P1810. This condition would occur more easily if the vehicle has not been started for an extended period of time because of torque converter drain back. DTC P1810 does not turn on the MIL the first failure, but does store the code and it commands maximum line pressure. The customer will probably notice only the harsh shift.
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