Prime: Let's Do This!

Way to go so far man, glad to hear you getting those miles finally! This Pete isn’t so bad starting forward but backing almost anywhere she does tend to like to get jumpy, nothing a little patience and using the differentials won’t help though. Stay safe!

Way to go so far man, glad to hear you getting those miles finally! This Pete isn’t so bad starting forward but backing almost anywhere she does tend to like to get jumpy, nothing a little patience and using the differentials won’t help though. Stay safe!

I agree completely with the patience suggestion.

However your reference to "using the differentials" ? As in "inter-axle differential lock"? There is only one...unless of course you are driving a tridem with 3 live-axles, which I know does not apply. So your suggestion this can help smooth out the rough spots while backing has peaked my curiosity.

Please explain what you mean by this. I have used the differential lock for very specific reasons, which I'd be happy to describe (and will based on your reply). But for basic "stable surface", garden variety backing,...I've never had a reason to lock the differential. So perhaps you can share a trick with me I am not aware of or haven't thought of. Wouldn't be the first time...

That said, getting accustom to the quirks of backing with an auto-shift tractor, the trick is to get the truck moving and leverage the physics of momentum in order to move the wagon into the hole. I know; "easier said than done"; because it requires a smooth flow, void of herky-jerky, frequent braking and throttle applications. Smooth backing comes with experience and hundreds of repetitions necessary to build the confidence required to move backwards at a steady/constant speed.

I’d like to be all fancy here and give a great answer, but I won’t cause it wouldn’t be right. That said I’ve had a few occasions where I just could not get rid off the backing jerks, so for whatever reason per my instructor, I engaged the inter axle diffs and performed the same backing maneuver again with out the jerking, or almost none. Wish I could explain it, but for whatever the reason, it worked. And no, wasn’t slippery surface or even gravel, both were relatively flat and going in at say 20-35 degree angle offset?.? Just seemed to help both times. That said, now that I’ve finally figured this trucks quirks out, I’ll be out of it very soon......

Bran, hope all is well, know your hitting some good miles but don’t forget us all in here!!

I’d like to be all fancy here and give a great answer, but I won’t cause it wouldn’t be right. That said I’ve had a few occasions where I just could not get rid off the backing jerks, so for whatever reason per my instructor, I engaged the inter axle diffs and performed the same backing maneuver again with out the jerking, or almost none. Wish I could explain it, but for whatever the reason, it worked. And no, wasn’t slippery surface or even gravel, both were relatively flat and going in at say 20-35 degree angle offset?.? Just seemed to help both times. That said, now that I’ve finally figured this trucks quirks out, I’ll be out of it very soon......

Bran, hope all is well, know your hitting some good miles but don’t forget us all in here!!

Thanks for the reply, I had all but forgotten this. No need for a fancy answer though, this was a really good answer as is. It was honest and based on some experience.

I actually tried this when spotting a backhaul load of water (46k lbs) on a flat level, dry surface, 45’ angle back. It did seem to spread out the rough spots and slightly improve throttle response. I guess it stands to reason by spreading out available torque to both drives instead of one, makes for a smoother transition between coasting and slight throttle applications.

The other times I use the “differential lock”:

- getting under a loaded trailer if it’s set a tad too low

- getting out from under a loaded trailer. This is especially effective when dropping on an incline (as found at most Walmart store docks). Compensates for the slow release of air from the bags and gets the tractor over the hump of the incline without the rear drive wheel’s spinning. (Like a beached whale)

- snow and ice, especially during coupling and uncoupling. When used in combination with the traction control override (knock on wood), I’ve never had issues getting under or out from under a trailer in snowpack and ice.

Just use caution to never engage or disengage the differential lock while the truck is moving (I know SG knows this, for others who may not).

Correction: never engage of disengage the differential lock if the wheels are spinning. It can be moving, but no wheel spinning.

Correction: never engage of disengage the differential lock if the wheels are spinning. It can be moving, but no wheel spinning.

So glad the differential lock was brought up on the other board. I think it was briefly mentioned in CDL School but not to the point that I really understood it. That's why I love these forums.