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Output speed sensor

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Peewee21

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could the vehicle output speed sensor affect the transmission shifting causeing it to be slow coming out of first gear
 
Ok i have changed the sensor and im still having the same problem with it being slow shifting but now the speedometer is acting up by showing im running 80mph before the truck sgifts out of second gear
 
No sir. Speedometer is read crazy and will het highbrnough to shut the truck down till it gets back down below 90
 
Little white box behind glove box. Talks to ECM, ABS, Radio and speedo. They can be repined or add a dip switch if needed.
 
Ok thank you. Do they have to be sent somewhere to be repinned and what is a dip switch sorry for a the questions i just dont know a whole lot about tranny stuff
 
The VSSB is not really part of the tranny. Rather it takes the speed sending unit's signal and adjusts it for the differential ratio (ex: 4.10, 3.73, etc) and then (as Leroy notes) passes this signal to the ECM, speedo, and radio (if you still have the original radio with speed controled volume adjustment).

The ECM will use the signal it gets from the VSSB to control the tranny's gear and TCC lock.

Given that the speedo seems like it is nuts and the ECM seems like it is acting in relation to the speedo, chances are that something is not correct with the VSSB. Whether it is the signal going to the VSSB (wiring), or the VSSB itself is the question.



Within the realm of possibilities is that some of the vehicle's grounding wires have corrosion and / or are no longer in their correct mounting location. Reason for mentioning the grounds is that they can cause lots of nutty behavior.



Consider cleaning all the grounds first (there are quite a few of them) and then focus on other items if it does not correct the issue.
 
They can be repined. The dip switch is a row of switches built into one housing that you can configure anyway you need. There are articles about it, do a google search on it.
I'd start with another VSSB and keep your original.
 
Sounds to me like you created a problem when you replaced the VSS. If it is an aftermarket part, the FIRST thing I owuld do is swap it out for an AC DELCO sensor. With the speedo acting up, you need to get that sorted out first. The VSSB converts the 40 pulse per driveshaft revolution signal into a 4,000 pulse per mile signal for the ECM and radio, and a 128,000 pulse per mile signal for the ABS. It does this via the jumper settings inside that it uses to convert the 40 ulse per driveshaft revolution signal into the correct number of pulses to obtain the required 4,000 pulses per mile and 128,000 respectively. It is a pretty basic device, but it can be affected by noise interference so make sure the wires going from the VSS(the sensor in the tailshaft of the transfer case) to the VSSB are twisted. If somebody has done wiring repairs, it is not uncommon for them to get untwisted which makes the low voltage signal suscepteable to noise interference. Also make sure the sensor end is compeltely clean with NO metal on it. Some metal flakes on the VSS is the most common reason to cause problems at slow speeds. many times all that is needed is to remove it, wipe it off, and reinstall it.

As to the slow to come out of 1st gear, this is a known issue with early 4L80E's to have a delayed 1-2 shift with a harsh engagement when it finally shifts. Is this what you were experiencing?
 
I replaced the vss because i thought that the was my problem with my speedo i bought it from the dealership.


The tranny shifts easy when it finally shifts out of first it was rebuilt less than 5000 miles ago and didnt start the slow shifting till the speedo started acting up
 
Peewee21 said:
I replaced the vss because i thought that the was my problem with my speedo i bought it from the dealership.


The tranny shifts easy when it finally shifts out of first it was rebuilt less than 5000 miles ago and didnt start the slow shifting till the speedo started acting up
Click to expand...
You were pretty vague in your 1st post, that's why I was trying to get some details. Have you tried cleaning and re-installing your origanal VSS? Have you checked for play in the transfer case where the slip yoke goes in? It isn't uncommon for the tail shaft bushing to get loose, let the tail shaft drop down, and this increases the clearance between the VSS and tone wheel making it slower to pickup and read when it is moving.
 
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