Sick 41TE

Hi All,

OK, this morning we are driving back from the beach, about an hours drive.
20 minutes from home,
idling in the morning rush, me driving of course, the van gives a bump and
the trans goes into limp mode,
stuck in 2nd gear.

We got home and after unloading the kiddies and wife and various bags and
such, I plugged in my
OTC 4000E scan tool into the CCD bus and asked the trans what is wrong.
Here's the error codes:

51 1st Gear Ratio Error
52 Turbine Sensor

I then cleared the codes and ran a general test, and got this:

Turbine RPM 732
Engine RPM 751

And here's the output from the clutch volume index:

LR 51
OD 57
24 53
UP 40


The OD which I assume is the Overdrive clutch, the scan tool lists a minimum
of
something like 73. The others are within their minimum/maximum.

Am I correct in my diagnosis that the overdrive clutch is worn, and during
the drive
this morning it slipped enough to the point that the turbine was turning
slow enough
as compared to the engine, that the trans computer decided that something
was
wrong and shut down the works?

If this is the case, then with this van there's an overdrive lockout button
that
disables overdrive (usually used for towing) My inclination right now is
to just turn this on to lockout Overdrive, and then keep driving the van
until
the transmission shreds itself, then get it rebuilt. Once I cleared codes
the
trans started operating normally. This van hardly ever goes out on the
freeway, and frankly I don't think my wife has been above 75Mph for the last
year
in it. (I don't think she's ever driven over 75Mph in any vehicle, for that
matter) Most of it is low-speed under-50Mph city street driving. Does
anyone have any dire warnings for me for this (aside from the smart-alecky
comments about gas mileage, that is)

This particular trans was rebuilt about 68,000-72,000 miles by the previous
owner,
about 10,000 miles before we bought it. It has 110,000 miles on it now. It
does have
a flashable trans computer. Unfortunately, the place that rebuilt the
transmission was
one of those transmission shops that doesen't believe in using ATF +3 in
these
transmissions. (they use Dexron plus a so-called friction modifier fluid)
so I wouldn't
put it past them that they didn't even change the clutches.

Ted

 

Turbine sensor = input speed sensor

Sounds like classic input speed sensor failure, Ted.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
adddress with the letter 'x')

 

$20-30 part and 20 minutes under the vehicle, or, alternatively, however
much the dealer thinks they can get out of you.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
adddress with the letter 'x')

 

Input speed sensor bad, I would recommend replacing both the input and
output sensor. Shouldnt cost no more then $80 for both pieces.
located at the front of the trans to just under the hoses that run to the
trans cooler.

Glenn Beasley
Chrysler Tech

 

I see both of them in my 41TE/AE trans book, easy enough to get at.
Good
advice on doing both, they probably wern't replaced by the rebuilder.

I took a look at the CVI ranges in my book, and I was interested to
see that the ranges Chrysler publishes are different than what the
OTC scan tool software displays on the scan tool. Per the scan tool
my OD number was out of range, per the Chrysler book it is in range.
That's the last time I'll trust a scantool to provide anything other
than the raw data figures.


Ted

 

Just an update, I replaced the Input speed sensor/Turbine sensor and it
seems to have fixed the problem. The CEL no longer comes on after high
speed driving (it had been coming on intermittently, with an EGR
failure
code using the off-on-off-on ignition key method of reading fault
cccodes)
but I can also tell shifting is improved. It used to be that when you
came to a slow low-speed stop that the van seemed not to want to shift
down and would hesitate slightly, I had always thought that normal
behavior.

I tried replacing the output sensor but the sensor I bought for that
(NAPA Echlin part# TSS100) didn't seem
to want to thread in properly so I didn't push it.

Both sensors were about $20 each at NAPA.

Ted

 

Nope, the turbine speed sensor is giving a different reading than the
engine speed (determined from the cam/crank sensors). Sounds like the
turbine (aka "input") speed sensor failure that we all know and love.
Should be an easy fix.