4l60e won't shift and my speedo quit working. Already replaced vss, but still not shifting. Does this truck have a vssb/drac? If so, would a faulty vssb cause these problems?

bad VSS (chevy) k1500 not Suburan. 4th gear dead.
NOT TOLD ALL 4wd or 2wd truck, and matters huge on VSS.
5.0L? no car mileage told or on tranny..
the scan tool tells you VSS is dead.,veh.speed,sensor.
the transmission shifts by lots of variables and FOR SURE SPEED, is one, so the would't cause is dead wrong;.
first thing to do is learn what box is there. (real name)
GM car is GM transmissions sure but which exact one.
and why do you ignore the speedo/tacho, they must work.
chevy 1999 k1500 4L60E RPO Codes M30
4L60e electrically shifted by the TCM brain (it or PCM/TCM)_
to shift electronically many things most work
VSS, and all speed sensors, and shift solenoids.
and more this code smacks of cam timing errors top me.
Trouble Code: P1345 (5.0L V8 VIN M Auto)
Crankshaft Position (CKP)-Camshaft Position (CMP) Correlation( < this word means OUT OF TIME in geek speak) the PCM predicts next cam pulse and is way the heck off time, and tells you it is and does not lie. OMG it has an old Distributor and CMP is bad or distributor ws never timed correctly as the SM directs.
SM= service manual.
this error can not be ignored, but back to transmission problem in drive
To shift up the TCM brain must know speed
in drive upshifts fail, hard.
I am reading your SM now. learning what version this 4L60 is
and all sensors and if it has line pressure control solenoid.
to get the VSS DTC error one must drive long time to get it.
but the speedo did not lie to you , VSS is dead.
yes it has PCsol PCS solenoid that sets main tranny line pressure just before the shift, ( 3 soles to shift , not 2)
as you go higher gears the main line pressure needed to do so needs lots more pressure
from 75PSI to 175 PSI in drive. if not gears fail.

now 2 photo to prove all this.
first is VSS then 2nd is PCsol.

S10 PICKUP , NOT BLAZER S10- , NO ENGINE TOLD
NO DRIVE LINE TOLD.! NO VIN TOLD.
ENGINE RUNS FINE?
DRIVES FINE AND ALL OTHER THINGS WORK
THIS IS ALWAY SQUESTION 1 FOR ANY ELECTRIC FAILURE.

4l60E TRANSMISSION? OR STICK SHIFT, iT MATTERS TOO.
THE 4L60 E HAS VSS VEH, SPEEDS SENSOR ON THE TAIL SHAFT OF THE BOX..
no speedo cables here. this year.
the cluster has 1 fuse, Marked INST-lps if blown the much of the cluster dies. means insturment lamps(LPS)

the question really is , all fuses good.
and if automatic trans
does the VSS go to the TCM (so it can shift right) then the TCM tells the ECU speed too. then it sense speed data to the cluster.
sadly the scans of the old paper book , are blurry and 100 pages long, i refuse to read all of those for all engines there
or transmissions not told.



NO FUSE JUST FOR IT.!!
1992
IS THE SPEEDO ONLY DEAD?
AND ALL OTHER CLUSTER THINGS WORK>? OR NOT.
oil gauge, fuel ,voltage meter, and odom? ,eng. temp?

ALL FUSES GOOD, IS FIRST. JUST CHECK THEM ALL NOT WORRY WHICH IS WHICH.

SPEEDO DEAD, OR BOUNCES OR STUCK HIGH. WHAT?

ODOMETER DEAD"MILES) DEAD? OR WHAT?
ING fuse must be good , goes to cluster too.
the book, deep looking shows
DRAC
vehicle speed sensor buffer;.

here it is, and it drives the cluster directly
so is sensor ,wiring or the buffer bad.
the signals are very weak so the board here is a Ampifier
it states vss to ecm, tcm and cluster.
so if the ECM cans show the VSS dead we know
the DRAC is bad or the sensor left hear is dead.
the red circle below is cluster INPUT VSS.

CHECK ALL FUSES. i CAN'T

VSS - vehicle speed sensor possible for the shifting an speedometer problem , don't know about PS . Are you referring power steering ? This would have noting too do with not shifting or speedometer not working .

is the vacuum hose off the modulator , I seen this before , ck youtube for more help

If your car is manual, clutch not releasing completely, loose or damaged shift linkage, insufficient transmission oil or oil is in poor condition, sticking or jamming gears, worn or damaged striking rod. Autozone, Advanced Auto, or O'reilly can scan/read your check engine code. Speedo faulty or vss speed sensor no longer works.

Im having trouble as well with shifting higher than second gear and me speedo doesn't work.checked all fuses replaced vss (both) and still no speedo or shifting. any ides would be great. I have power at buffer and tranny

Hello wsarah03,

There is a Vehicle Speed Sensor (VSS) mounted on the transaxle, that is a good place to start. The VSS tells the powertrain management system when and how to shift the transmission and also gives the speedometer it's signal.

From your description that the speedometer quit working at the same time I would suspect the a faulty VSS.

Regards,
netvan

thats an interesting problem, i would be looking for either a pinched wire or i would also look at the plastic gear on the end of the vss they must be the same color and they should be interchangeable if the are not the same, and while you have the vss out look inside the hole where it goes and make sure the drive gear for the vss is still intact inside the tranny. The reason the tranny does not shift is because of the speedo not working the computer needs to know how fast the car is moving to determine the proper shift points for the tranny.Hope this helps

YES / VSS ON TRANS GIVES TRANS CONTROLLER SIGNAL TO SHIFT.ABS RUNS SPEEDO