Shifting with Jake brakes on.

BS.... most Jakes are set to cut out on their own at about 800 RPM's.

 

Diesels don't have compression braking by way of design, that's why they started putting Jakes on them. No, you shouldn't run them in town, simply out of consideration for the general public. But to have the "no engine braking" sign at the top of a hill is just plain ignorance on the part of lawmakers, who have zero experience with coming down a hill with a full load, and losing your brakes. If they did they'd think a bit before they did that. It would help if drivers had sense enough to shut them off in town. I've been on the road since I was 2 months old, so it's kind of a comforting sound to me, I also kind of like the feel of the engine idling when I'm trying to take a nap, I guess I just associate it with having my grandfather nearby, and he was my only father figure.
It's all his fault I'm out here, just one of the many things I have to thank him for, other than getting my own truck, I wouldn't change a thing about my life. Sorry for getting off track.

 

following in your path off the OP's original thread; are you saying that having your own truck has been the only thing you've regretted in terms of what he has provided you with?
I'd like to think I'd never go back to working a company truck. Wish I would have gotten one sooner; but I wouldn't have the appropriate level of maturity nor experience had that situation occurred earlier in life.

 

Getting back to the point of the post, I am wondering why it matters if the Jake switch is on or off when I up shift. As the Jakes only come on when your foot is off the fuel, why would they ever come on when you up shift? When up shifting I only let off the fuel enough to drop the engine RPMs by about 300 make my shift and then fuel back up. When down shifting I do use the Jake to drag the RPMs down by that same amount then fuel up to grab the next gear and continue slowing to do it all again. Most of the time, unless I misjudge the distance to a corner or something unexpected happens, I will only touch the foot brakes after I have pushed in the clutch and am rolling to a stop. I drive both our 3406B and our 6NZ C15 the same way, though I shift the 6NZ at lower RPMs. Am I doing something wrong? These are the first two trucks in what I hope to grow into a 20 unit company, so my future depends on these motors and the trucks they are wrapped in. Someone please point it out if I have got it wrong. Thanks

 

The reason why I don't shift up or down with the jakes on is because my gut instinct tells me not to. In my opinion it puts unecessary shock and stress on the driveline not much different from the goofballs that stomp and romp through gears racing a truck up to speed through redlights. I spent about $1300 on brand new spicer ujoints and driveshaft rebalancing this past spring. One ujoint cost about $200 the bolt kits are about $25 apiece. Plus I wonder what would happpen on a jake shift with some sort of bad jake failure. I had a spring break in one of my jakes this summer but nothing really bad happened. To me it's just commonn sense. Dont do it.

 

ON when I need them, and off when I don't. I know they work at the flip of the switch.

 

Some of our trucks shift WAY better with them on. It helps keep the smaller engines we use in their sweet spot. Some of the Meritor trans we've been getting lately DON'T LIKE IT AT ALL! I would think with a bigger engine you don't generally need to run them all the time, but it sounds sooo good!

 

To answer your first question some drivers use it to kill the rpm's down quicker to make the shift faster.....Say your taking off on a hill...lets just say you up shift at 1700rpm's..dropping in gear around 1400rpm's..Now, turn your jake on and allow it to engage between the shift and see how much faster you'll make your shift..Allowing the jake to engage while shifting just speeds up the shift, thats all, and it will in NO way damage your engine or drive train if done properly. 1 other thing about pushing the clutch and rolling to a stop..Do NOT hold the clutch in while rolling, if your going to roll to a stop, take the truck out of gear and let the clutch out. Never hold the clutch in while the truck is moving, not even just at a drift...this is how clutch brakes are burnt out. Trying to build a trucking company is hard now days, all the rules and regs are without a doubt designed to put small company's under, and they are very successful at it. One thing I would tell you is stay on top of your trucks...no matter how simple a problem may seem, treat it like its a major problem, let nothing ride till a later date, pay your drivers well, but higher the best, most experienced drivers you can find that hasent had more jobs than fingers they posses. Good luck!