So hey guys, what a beautiful day it was here. Low 80's, moderate humidity, great day to go for a drive in my '88 F800. 7.8 l Ford diesel, 5 x 2.
Thought I'd even take John along for a ride;
So there I was, just cruising along, minding my own business, running up that hill in 4 low at 1500rpm (who cares if about 50 cars are piled up behind me, I'm having fun) and it happened. Rear end jumps out of low into high, I immediately clutch it, it goes back into low and I continue on my now, not so merry way. So what's the deal?
Vacuum leak?
Newer style, electrically actuated.
Hi doublewide, Came across this on U tube while I was looking for videos on the deere 450d like mine. Is this your dozer? Sure looks like it. https://youtu.be/Zz-v9e6opJw
Time to have a look at the 2 speed motor, make sure the switch inside the motor is in good condition and the big spring. Don't know if that's new enough to have the new style snap action switch. Could be the shift collar didn't make it in all the way when you shifted, or it's possible the shift collar is getting worn inside the diff and wants to pop out.
Sure does norite , right down to the Rockland root rake brackets. And sure looks like the guy I bought it from. He told me that he and his dad bought it new and only used it on the farm to strip loam. His kid painted it just before I bought it, only 1800 hrs. Thanks for finding that for me!
Thanks lantraxco , I was thinking that it just didn't make a full shift, trying to down shift to fast on that hill to keep up my momentum. I'll be heading over to see the mechanic today. Thanks again.
I have done that myself in exactly that way, rushing it. Sure makes my teeth clench when they pop out like that! Drove one old truck that had that vacuum shift, spring return, you really had to feel your way with that.... on a hard pull you had to let the throttle slam shut for a couple seconds to build enough vacuum to make it work sometimes! LOL
Yeah, what a great idea, let's run everything off of engine vacuum!, how about windshield washers, why not, or how about that hydro boost setup, that was a really good idea, engine dies, loose your brakes!
Opened up the selector switch on the shifter, Contacts look clean...
Replaced the selector switch. Didn't really seem to make a difference. Hasn't really been a problem, just have to clutch it a few extra times to give it a chance to finish the shift. Seems to happen most when things have not quite warmed up yet. Not sure. Probably get into the rear end this winter.
Does that rear end have 80-90 gear oil, I would use 75-90 IMO.
There's a double limit switch inside the motor that may be worn or malfunctioning, there's an updated version that's a snap action instead of momentary, easy to check usually you can just pull a few screws and pop the sheet metal cover off... you will get some gear oil out of there sometimes. When the motor runs far enough for the shift unit to hit the end of travel the switch opens to stop the motor, one set of contacts at each end. There's also usually a heavy clock spring in there that the motor winds up in whichever direction it's moving while it waits for you to declutch or let off the throttle... these can be weak, deformed, or broken.
Truck Shop , will take that under advisement, thanks for the input.
Thanks Lantraxco will check that stuff out.