4r70w Speed sensor (oss) not reading - 04 mustang

JoColtrane

Newbie
Joined
May 31, 2021
Messages
2
Points
1
Make
Ford
Model
Mustang
Year
2004
Miles
61000?
Engine
6 cy 4.6?
4r70w speed sensor (oss) not reading. Tested wiring and sensor and readings were within spec. Removed sensor and took picture inside of port and was expecting to see ring gear but instead saw this and am unsure of what I'm looking at (see pic). Is this normal?

IMG_3485.JPG
 

billr

wrench
Staff member
Joined
Mar 12, 2007
Messages
7,197
Points
63
I think that is normal, but not sure. I think the OSS senses notches on a clutch drum. Rotate the output shaft and peek in there some more. We have a trans expert here who would know, for sure, but may not be back until after the holiday.

PS: if this is a V-6, it is probably the 4.2L engine
 

billr

wrench
Staff member
Joined
Mar 12, 2007
Messages
7,197
Points
63
Is your sensor on the main trans case, or the tail-shaft housing? Sensing the clutch drum would be on the main housing.
 

JoColtrane

Newbie
Joined
May 31, 2021
Messages
2
Points
1
Bill appreciate the reply. Let me further explain. Trans is installed and in the air so not sure if I can rotate right now. This is the OSS which is on the main housing. VSS is on the tail shaft. Trans is not shifting out of 1st gear and all other sensors appear to be working. At first I thought car was in limp mode due to TPS but fixed that. Speed sensor is the only sensor not registering a reading therefore computer doesn't know to shift but wiring and sensor tested within range. So next step was look in port but wasn't really sure what I was looking for. Electronic sensor (not mechanical).

Jo
 

billr

wrench
Staff member
Joined
Mar 12, 2007
Messages
7,197
Points
63
I'm going to send PM to our trans expert, see if I can bring him in early. This is a more serious problem than I first understood. With the advice of the guy I am summoning, I completely tore down and fixed a 4R70W about a year ago, so am familiar with the innards, but by no means an expert; just an experienced DIYer.
 

bp042665

hunting nut
Joined
Nov 26, 2012
Messages
721
Points
18
Location
Iva South Carolina
ok first off we need to verifiy its the right sensor the depth could be wrong so its not reading the transmission is moving do you have a scanner with live data if so drive and read
 

Mealticket

Full Member
Joined
Dec 31, 2016
Messages
99
Points
8
Age
48
Yeah, I just watched 2 Gary Ferraro videos and there is an early 2004 and a late 2004 OSS, and the teeth it's reading on the ring gear are not the same. They don't interchange. Check out the videos. In his case the issue came from swapped in trannies, but your sensor could be wrong.

MT
 
Top