E4OD, anyway to bypass VSS switch on differential? - Ford Truck Enthusiasts Forums



1987 - 1996 F150 & Larger F-Series Trucks 1987 - 1996 Ford F-150, F-250, F-350 and larger pickups - including the 1997 heavy-duty F250/F350+ trucks

E4OD, anyway to bypass VSS switch on differential?

Reply
 
 
 
LinkBack Thread Tools Search this Thread
  #1  
Old 08-15-2014, 12:36 PM
Realslowww Realslowww is offline
Elder User
Thread Starter
 
Join Date: May 2010
Posts: 848
Realslowww is starting off with a positive reputation.
E4OD, anyway to bypass VSS switch on differential?

I have a 1994 F350 with a E4OD and the trans started acting up, the speedo went out and the trans started doing all kinds of funny stuff and I have narrowed it down to the VSS in the rearend.

Is there anyway to bypass the switch and get the trans to work correctly? is it me or should a 10$ plastic part not have this kind of control over a machines operation.

Thanks for any help.
Reply With Quote
  #2  
Old 08-15-2014, 12:45 PM
ifrythings's Avatar
ifrythings ifrythings is offline
Senior User
 
Join Date: Aug 2011
Posts: 476
ifrythings is gaining momentum as a positive member of FTE.
That part will kill the tranny too if you don't fix it, thats the only thing that tells the computer how fast the truck is going, it like you driving with your eyes closed, wont be pretty.

As for a 10 dollar part, that is going to be garbage at that price, if you want it to work and last a long time, go get an oem one and save your self the hassle of crap parts

Before doing any of that, pull the sensor out the diff and make sure its clean, can be something that simple
Reply With Quote
  #3  
Old 08-15-2014, 02:11 PM
Realslowww Realslowww is offline
Elder User
Thread Starter
 
Join Date: May 2010
Posts: 848
Realslowww is starting off with a positive reputation.
Thanks, there are no descent after market parts?
Reply With Quote
  #4  
Old 08-15-2014, 05:14 PM
rla2005's Avatar
rla2005 rla2005 is offline
Post Fiend
 
Join Date: Oct 2005
Location: Illinois
Posts: 12,149
rla2005 has much to be proud ofrla2005 has much to be proud ofrla2005 has much to be proud ofrla2005 has much to be proud ofrla2005 has much to be proud ofrla2005 has much to be proud ofrla2005 has much to be proud ofrla2005 has much to be proud ofrla2005 has much to be proud of
Before you start down this path further please explain how you "narrowed it down to the VSS in the rearend." ?

They rarely go bad, it's usually a wiring issue or something else is dragging down the signal (RABS, Speed Control servo) or the PSOM is bad.

In the event it is a faulty VSS it is highly recommended to use an OEM replacement. Yes, the aftermarket versions are that bad...
Reply With Quote
  #5  
Old 08-15-2014, 05:15 PM
Diesel_Brad's Avatar
Diesel_Brad Diesel_Brad is offline
Post Fiend
 
Join Date: May 2009
Location: Gilbert, PA
Posts: 18,767
Diesel_Brad has much to be proud ofDiesel_Brad has much to be proud ofDiesel_Brad has much to be proud ofDiesel_Brad has much to be proud ofDiesel_Brad has much to be proud ofDiesel_Brad has much to be proud ofDiesel_Brad has much to be proud ofDiesel_Brad has much to be proud ofDiesel_Brad has much to be proud ofDiesel_Brad has much to be proud of
The VSS sensor is fairly common to go bad
Reply With Quote
  #6  
Old 08-15-2014, 05:31 PM
rla2005's Avatar
rla2005 rla2005 is offline
Post Fiend
 
Join Date: Oct 2005
Location: Illinois
Posts: 12,149
rla2005 has much to be proud ofrla2005 has much to be proud ofrla2005 has much to be proud ofrla2005 has much to be proud ofrla2005 has much to be proud ofrla2005 has much to be proud ofrla2005 has much to be proud ofrla2005 has much to be proud ofrla2005 has much to be proud of
Quote:
Originally Posted by Diesel_Brad View Post
The VSS sensor is fairly common to go bad
I will kindly disagree

I know I have replied to many posts where the OP stated they already replaced the VSS but still have the same issue. Yes, they do go bad but before spending the bucks on one it is easier on the wallet to look at the other more common causes.

I think subford holds the record for most "assists" with this issue!
Reply With Quote
  #7  
Old 08-15-2014, 07:42 PM
Realslowww Realslowww is offline
Elder User
Thread Starter
 
Join Date: May 2010
Posts: 848
Realslowww is starting off with a positive reputation.
Thanks for the replies, the speedo and eletronic mile gauge quit working.
Reply With Quote
  #8  
Old 08-15-2014, 07:50 PM
FORDF250HDXLT's Avatar
FORDF250HDXLT FORDF250HDXLT is offline
Post Fiend
 
Join Date: Jul 2006
Location: Maine/Oklahoma
Posts: 15,159
FORDF250HDXLT has a brilliant futureFORDF250HDXLT has a brilliant futureFORDF250HDXLT has a brilliant futureFORDF250HDXLT has a brilliant futureFORDF250HDXLT has a brilliant futureFORDF250HDXLT has a brilliant futureFORDF250HDXLT has a brilliant futureFORDF250HDXLT has a brilliant futureFORDF250HDXLT has a brilliant futureFORDF250HDXLT has a brilliant futureFORDF250HDXLT has a brilliant future
start with the basics.check your fuses.

Quote:
Originally Posted by Diesel_Brad View Post
The VSS sensor is fairly common to go bad
people often replace them.however most of the time needlessly.
Reply With Quote
  #9  
Old 08-15-2014, 07:50 PM
Blurry94's Avatar
Blurry94 Blurry94 is offline
Moderator
 
Join Date: Jun 2003
Location: Calhoun GA
Posts: 3,111
Blurry94 has a very good reputation on FTE.Blurry94 has a very good reputation on FTE.Blurry94 has a very good reputation on FTE.Blurry94 has a very good reputation on FTE.
Quote:
Originally Posted by Diesel_Brad View Post
The VSS sensor is fairly common to go bad
Agreed.

You can use a scan tool that accepts DTC input to verify if the ECU is getting a speed signal (MPH) input.
Reply With Quote
  #10  
Old 08-15-2014, 07:58 PM
rla2005's Avatar
rla2005 rla2005 is offline
Post Fiend
 
Join Date: Oct 2005
Location: Illinois
Posts: 12,149
rla2005 has much to be proud ofrla2005 has much to be proud ofrla2005 has much to be proud ofrla2005 has much to be proud ofrla2005 has much to be proud ofrla2005 has much to be proud ofrla2005 has much to be proud ofrla2005 has much to be proud ofrla2005 has much to be proud of
Quote:
Originally Posted by Realslowww View Post
Thanks for the replies, the speedo and eletronic mile gauge quit working.
Quit working like no needle movement and blank odometer display? If so check fuses 8 and 18.
Reply With Quote
  #11  
Old 08-15-2014, 08:23 PM
subford's Avatar
subford subford is offline
Post Fiend
 
Join Date: Aug 2005
Location: Easton,Ks
Posts: 19,797
subford has much to be proud ofsubford has much to be proud ofsubford has much to be proud ofsubford has much to be proud ofsubford has much to be proud ofsubford has much to be proud ofsubford has much to be proud ofsubford has much to be proud ofsubford has much to be proud ofsubford has much to be proud of
Quote:
Originally Posted by Diesel_Brad View Post
The VSS sensor is fairly common to go bad
It is almost imposable for a VSS to go bad unless you break it while removing it or it is hit by something in the rear end.

Sometimes it has been installed wrong with too large a gap or has something build up on it as it is a magnet.

Not sure how it would loose it magnetism but that may be possible somehow.

If someone or some part in the PSOM or RABS puts power to the VSS wires that could burn open the coil in the VSS. The VSS supplies its own power.

The VSS just consists of a permanent magnet, a ferromagnetic pole piece, a pickup coil, and a rotating toothed wheel. No moving parts in the VSS.
As the tone wheel teeth of the rotating tone wheel pass by the face of the magnet, the amount of magnetic flux passing through the magnet and consequently the coil varies. When the tone wheel tooth is close to the sensor, the flux is at a maximum. When the tooth is further away, the flux drops off. The moving target results in a time-varying flux that induces a proportional voltage in the coil. Subsequent electronics (PSOM & RABS module) are then used to process this signal. The PSOM then drives the Speedometer, updates the mileage in the LCD odometer display and the EEPROM and sends a digital waveform to the Speed Control and the PCM Computer..
Reply With Quote
  #12  
Old 08-15-2014, 08:26 PM
Diesel_Brad's Avatar
Diesel_Brad Diesel_Brad is offline
Post Fiend
 
Join Date: May 2009
Location: Gilbert, PA
Posts: 18,767
Diesel_Brad has much to be proud ofDiesel_Brad has much to be proud ofDiesel_Brad has much to be proud ofDiesel_Brad has much to be proud ofDiesel_Brad has much to be proud ofDiesel_Brad has much to be proud ofDiesel_Brad has much to be proud ofDiesel_Brad has much to be proud ofDiesel_Brad has much to be proud ofDiesel_Brad has much to be proud of
I am speaking from personal experience.

I have replace at least 50 VSS sensors and it fixed the speedometer issues, shifting issues or other related issues. Out of the 50 or so that I have replaced, not ONE did not fix the issues.

When you work at a dealer, you see all sorts of common issues
Reply With Quote
  #13  
Old 08-15-2014, 08:59 PM
subford's Avatar
subford subford is offline
Post Fiend
 
Join Date: Aug 2005
Location: Easton,Ks
Posts: 19,797
subford has much to be proud ofsubford has much to be proud ofsubford has much to be proud ofsubford has much to be proud ofsubford has much to be proud ofsubford has much to be proud ofsubford has much to be proud ofsubford has much to be proud ofsubford has much to be proud ofsubford has much to be proud of
Quote:
Originally Posted by Diesel_Brad View Post
I am speaking from personal experience.

I have replace at least 50 VSS sensors and it fixed the speedometer issues, shifting issues or other related issues. Out of the 50 or so that I have replaced, not ONE did not fix the issues.

When you work at a dealer, you see all sorts of common issues
You realize what you are saying goes against just about all of the post on this subject in this Forum in the last 7 years that I have been reading.

I have also fixed numerous problems with the PSOM signal going to the transmission and speedometer and I did not replace one VSS.

What you are saying is very hard for me to believe.
Reply With Quote
  #14  
Old 08-15-2014, 09:10 PM
FORDF250HDXLT's Avatar
FORDF250HDXLT FORDF250HDXLT is offline
Post Fiend
 
Join Date: Jul 2006
Location: Maine/Oklahoma
Posts: 15,159
FORDF250HDXLT has a brilliant futureFORDF250HDXLT has a brilliant futureFORDF250HDXLT has a brilliant futureFORDF250HDXLT has a brilliant futureFORDF250HDXLT has a brilliant futureFORDF250HDXLT has a brilliant futureFORDF250HDXLT has a brilliant futureFORDF250HDXLT has a brilliant futureFORDF250HDXLT has a brilliant futureFORDF250HDXLT has a brilliant futureFORDF250HDXLT has a brilliant future
it doesn't make any sense because that's not a ware item.if the 50 replacements cured the shifting issues,then more than likely simply cleaning the sensors,rather than replacement would have done the same thing.it's actually pretty easy to know when one is in need of cleaning,as the speedometer needle will be bouncing.once it gets so bad,it will start to frig up the trans operation because the control unit can't read the speed accurately.
however i can easily see how a steelership wouldn't bother with such things.they would want to simply change the sensor so they could charge for the part and the labor to replace it.they didn't get their derogatory nickname for nothing.
Reply With Quote
  #15  
Old 08-15-2014, 09:28 PM
BruteFord BruteFord is offline
Postmaster
 
Join Date: Mar 2013
Location: Over There
Posts: 3,069
BruteFord has much to be proud ofBruteFord has much to be proud ofBruteFord has much to be proud ofBruteFord has much to be proud ofBruteFord has much to be proud ofBruteFord has much to be proud ofBruteFord has much to be proud ofBruteFord has much to be proud of
OT question, could a early TC or tail housing be swapped in and the speedo pickup version used instead to get the sensor off the rear end?
Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
1994: stored Code 452, VSS signal too small, & E4OD trans Torky2 1978 - 1996 Big Bronco 22 05-22-2016 09:52 AM
VSS Issue slashfan7964 1987 - 1996 F150 & Larger F-Series Trucks 2 04-03-2016 09:40 PM
F-Super Duty VSS removal? Phy Pre-Power Stroke Diesel (7.3L IDI & 6.9L) 12 12-11-2014 01:06 AM
1991 E4OD OD button wiring? kobaltblue Pre-Power Stroke Diesel (7.3L IDI & 6.9L) 3 05-02-2012 01:12 PM
overdrive cancel switch...? fkaster01 Clutch, Transmission, Differential, Axle & Transfer Case 10 04-03-2009 07:24 PM


Go Back   Ford Truck Enthusiasts Forums >

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Forum Jump


All times are GMT -5. The time now is 03:56 AM.


This forum is owned and operated by Internet Brands, Inc., a Delaware corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford Motor Company or its related companies in any way. FordŽ is a registered trademark of the Ford Motor Company.