auto trans won't downshift to 1st gear on 2000 Explorer V6 SOHC

Any ideas on why my auto trans won't downshift to 1st gear when manually
placed into 1st gear. It will limit itself to first gear only when
accelerating in 1st gear but it won't allow engine breaking to decelerate
on decents. It seams like it is in neutral when no gas is applied, allow
it to coast and even pick speed on a steep decent. Problem only occurs
after the engine has warmed up. 2nd gear functionality works fine
including engine breaking. Vehicle is a 4x4 with Auto/Hi/Lo transfer case
and a 4.1 LS diff.

Thanks, Jeff

Straight from the 2000 WSM for the 5R55E transmission....

"If this position is selected at normal road speeds, the transmission will
shift into third gear, then into first when the vehicle reaches a speed
below approximately 48 km/h (30 mph)."

As far as no engine braking... are there any other symptoms or concerns? Has
the TCM been scanned for codes (this will require something a bit upscale
from a dimestore scan tool)? Is the concern founded in fact or in
perception?




"KI0FT" > wrote in message
lkaboutautos.com...
> Any ideas on why my auto trans won't downshift to 1st gear when manually
> placed into 1st gear. It will limit itself to first gear only when
> accelerating in 1st gear but it won't allow engine breaking to decelerate
> on decents. It seams like it is in neutral when no gas is applied, allow
> it to coast and even pick speed on a steep decent. Problem only occurs
> after the engine has warmed up. 2nd gear functionality works fine
> including engine breaking. Vehicle is a 4x4 with Auto/Hi/Lo transfer case
> and a 4.1 LS diff.
>
> Thanks, Jeff
>
>

Thanks for your response to my question!! When the trans is manually
placed into 1st it never indicates when it does drop into first. I expect
the RPM to rise quickly when it does eventually drop into 1st. The problem
occurs when deceleration or when decending a hill. The RPM just sits at
idle until I give it the gas to start an acceleration. No other symptoms.
Again - it works fine when its cold but promptly begins to fail when normal
running temperature is reached.

On Wed, 22 Dec 2004 19:24:44 -0500, "KI0FT" >
wrote:

>Thanks for your response to my question!! When the trans is manually
>placed into 1st it never indicates when it does drop into first. I expect
>the RPM to rise quickly when it does eventually drop into 1st. The problem
>occurs when deceleration or when decending a hill. The RPM just sits at
>idle until I give it the gas to start an acceleration. No other symptoms.
>Again - it works fine when its cold but promptly begins to fail when normal
>running temperature is reached.

It seems to me that there was a TSB on this or a similar problem a
couple years ago. It was a problem in the valve body and was being
fixed under warranty. There was definitely something posted on it,
try a google search in this newsgroup.
--
Elbridge Gerry, of Massachusetts:

"What, sir, is the use of militia? It is to prevent the
establishment of a standing army, the bane of liberty. . .
Whenever Government means to invade the rights and liberties of
the people, they always attempt to destroy the militia, in order
to raise a standing army upon its ruins." -- Debate, U.S. House
of Representatives, August 17, 1789