Bob Beauchaine

Mine only moved less than 1/4" - it wasn't loose - that is the nut moved a 1/4" clockwise. The problem was first noticed on 4X4s but has worked on both 2 and 4 wheel drive Getrag powered trucks. If you can move it at all it just might do the trick.

Bob

I just looked up the torque rating for the yoke nut - 280 ft. lbs. that is right out of the tech manual.

gcliburn

So on a 4wd would the nut to check be on the rear output of the transfer case? Sorry if this sounds dumb, but just wanted to check.

chadstpierre

Hello, New Update...

We are sure this nut is tight because we had to replace the output shaft bearing, and when he put it all back together it was all tight. But when we got this truck the cruise control always acted this way. Now, below I have some updated information on what things we checked up tell now. The things you guys are suggesting we are checking here.

Truck: 1992 Dodge Standard 5 Speed
Tranny: Getrag

+++Symptoms+++
When cruise control is engaged, when going up hill cruise maintains smooth steady cruise speed. When on flat surfaces cruise control becomes erratic and system unable to maintain steady/smooth control speeds. When going down hills cruise system unable to maintain smooth steady cruise speed. Erratic cruise speeds does not change with increased or reduced speeds.

Things we tested...

==Vehicle Speed Sensor (VSS)==
-This sensor was replaced with a new one with same cruise control problems.
-Voltage direct from this sensor read on the Orange wire and Red/Blue wire read 4.5Volts. According to a tech book the VSS signal should read 8Volts... But this book we are reading from is for trucks of year 1994, so we don't know what the correct VSS sensor output voltages should be. The VSS on the 94's have three wires, and this 1992 has only 2 wires. What should the correct voltage be from the VSS on the 1992 truck?

==VSS Gear==
-The gear is in great shape with no cracking, and all teeth are intact and not stripped.

==Vacuum Test==
-Tested vacuum and getting very strong vacuum reading of close to 30 InHg. -This test was performed by removing the vacuum hose from the Cruise Control Servo, and connecting a vacuum gauge to it.
-A steady vacuum is present when the vehicle is turned off.

==Cruise Control Servo==
-Disconnected the servo for testing.
-Connected the Blue wire to Battery positive, and the remaining terminals to ground. This causes the servo to work with out it being connected to the cruise system.
-Vacuum applied to the servo.
-Electrical connections connected.
-When voltage is applied to servo, the servo reacts by pulling away from the throttle linkages. Servo appears to work correctly.
-Checked to see if servo maintained steady pressure. It does.
-Servo has no leaking vacuum
-When voltage is disconnected from servo, the cable releases and the cable moves out towards the throttle linkage.
-Servo does not jitter, or move erratically when in test mode.

==Throttle Linkages==
-Checked that all linkages were tight, found that the ball bushings rod was sloppy. Replaced/Readjusted. Added spacer to the linkage, and throttle linkage is now tight with no play.
-Same Erratic Cruise speeds occur.

==Cruise Control System==
-System functions such as resume, accelerate, decelerate, stop, and brake switch seem to work fine.

Things we need to check or need to know....

*What is the correct voltage of the VSS?
*What is the correct voltage for cruise control from SBEC/PCM? Need clarification on how to test this system for correct voltages and signal voltages for VSS and main computer system.
*Possible defective control module/SEBC/PCM?
*Improper electrical signal from VSS to control module/SEBC/PCM?

What we think might be the problem...

At this point we have tested many mechanical items, the mechanical items appear to be working correctly; however the signals or path ways that the signals are transfered on may be interfered with or not working correctly, or the Computer system in the truck is not interpreting te signals from the VSS or Cruise Control Servo correctly.

Please let me now what you think, if any one can help us out with the voltages in the "Things we need to check" section, please let us know. Maby we can get one step closer to solving this issue as I know many of you out there are experiencing the same problem with the Cruise Control.

Thanks you very much,


Chad

wannadiesel

I would try a bleed or an orifice in the vacuum line to slow the action of the servo. What I think is happening is that the cruise calls for more speed, but the turbo lag keeps the truck from speeding up as quickly as the PCM expects - so it calls for even more throttle. About that time, the turbo spools, the truck takes off, and the PCM says "Oh crap, we're going too fast!" and chops the throttle. Truck slows down and the whole cycle repeats until you are seasick and turn off the cruise.

Ace

Maybe OT depending on how you look at it, but I just got back from around a 900 mile round trip tour through the Black Hills and I could not believe how well my simple hand throttle worked as a cruise control. Pretty easy to set the throttle and hold desired speed on the straight and level. It would run up around 6-8mph on the down grades, and take just a slight goose or additional peddle pressure to hold steady on the uphills. The 5.9 has so much torque it cruises almost effortlessly unloaded. Can't imagine why anyone would suffer the pains of repairing the stock cruise control if it took more than five minutes to figure it out. Just a thought.

http://72.19.150.167/PhotoAlbum/Cars/Pics/CTD_84.jpg
http://72.19.150.167/PhotoAlbum/Cars/Pics/CTD_85.jpg