Delayed engagement in automatic
Delayed engagement in automatic
"Friend" borrowed my 2002 Ranger and returned it with grill assembly destroyed, left front blinker gone and hood damage. He says he hit a deer but who knows.
Experiencing a 5-8 second delay before the truck engages in any gear and does so with a very strong jolt. In drive it sorta crawls forward prior to jolt but in reverse no movement prior to the big bang.
Hard not to connect this to the smashed up front. Appreciate any advice.
Dipstick shows red fluid covering the hatched area but not above. I did it on cold. There WAS smoke coming out of the engine on the left side facing the vehicle, this was over the summer and he said it was a missing cap or something.
Last edited by ksteele; Mar 30, 2022 at 04:20 PM.
Welcome to the forum
The delay and harsh engagement means the pressure in transmission is low
All automatics run on ATF pressure, the pressure engages the bands and clutches
Forward requires minimum 100psi to engage
Reverse minimum 150psi to engage
This is why Reverse is often first to show slow to or won't engage, when there is an internal pressure issue on any automatic, not a Ford thing
Changing the fluid and filter, and inspecting the old fluid is a start, little metal bits would be a sign its more than just a pressure issue, parts are breaking apart
There is an EPC(electronic pressure control) solenoid in 1995 to 2011 Ranger automatics, rarely an issue but can be changed with pan off
The Valve body gaskets and seals are the usual culprit for low pressure, and it can also be changed with pan off
Any transmission shop can hook up pressure gauges to the external ports and diagnose where/when the pressure is being lost
And no, none of this could be caused by a front end collision or any type of collision
Generally its just miles adding up, or overheating the transmission pulling loads, this can cause issues with the gaskets and seals that maintain the internal pressure
The delay and harsh engagement means the pressure in transmission is low
All automatics run on ATF pressure, the pressure engages the bands and clutches
Forward requires minimum 100psi to engage
Reverse minimum 150psi to engage
This is why Reverse is often first to show slow to or won't engage, when there is an internal pressure issue on any automatic, not a Ford thing
Changing the fluid and filter, and inspecting the old fluid is a start, little metal bits would be a sign its more than just a pressure issue, parts are breaking apart
There is an EPC(electronic pressure control) solenoid in 1995 to 2011 Ranger automatics, rarely an issue but can be changed with pan off
The Valve body gaskets and seals are the usual culprit for low pressure, and it can also be changed with pan off
Any transmission shop can hook up pressure gauges to the external ports and diagnose where/when the pressure is being lost
And no, none of this could be caused by a front end collision or any type of collision
Generally its just miles adding up, or overheating the transmission pulling loads, this can cause issues with the gaskets and seals that maintain the internal pressure
Great info thanks. I just drove it to my local shop and it had no power, it felt like driving a manual in 1st gear on a highway. Reverse gives the biggest jolt when it engages and today it took a good 10-12 secs. I'll pass this onto my service guys, they are quite good.
Thread
Thread Starter
Forum
Replies
Last Post
Bjenks
Drivetrain Tech
2
Nov 20, 2021 07:28 PM



