Understanding downshifting

There are different ways that you can do it.

The simplest really is with the RPMs. If you downshift with the RPMs too high you won't be able to get it into the lower gear.

If the RPMs are too low the engine will start to Lug and you don't want to be there.

Just bear in mind if you downshift going downhill the truck is going to speed up and that's going to alter your shift.

Likewise if you downshift going up the hill the truck is going to slow down and that also is going to affect the timing of your shift.

I hope that does not confuse you but it's something to think about.

 

I'm same as the other replies, depending on situation. Say flat ground, upshift at 1500, in gear at 1100. Downshift at 1100, in gear at 1500. That's high range on a 15210B Eaton Fuller. Low range is the same thing, except it's roughly a 200 rpm split instead. When I upshift in low range, I still generally pull it out of gear at 1500, skip a gear, and go into gear at 1100. For example, from first to third is a 400 rpm drop.

When I'm grabbing gears to slow down, I stay on the brakes with the left side of my right foot, and I work the throttle with the right side.

 

Only really use Mph if you are decelerating rapidly due to say a traffic jam ....you can’t just keep downshifting in order 9-8-7-6....therefore you need to use mph to guide you......otherwise use RPMs

(In the example you said about slowing to 25 before going from 8 to 7) I’m guessing you doing that due to the “7=25 rule”
But if you use RPM “400” rule then you can downshift to 7 at the 30mph mark .....
At 30mph in 8th ; you’re roughly around 1100 Rpm....if you add the 400 then you have 1500 rpm ....Can you shift at 7 then? You Sure can....because the 400 put you the ideal engine range 1100-1500 RPMs.

So just look at your RPMs. And use the 400 rule

@1200 Rpm at any speed gives you 1600 that you need to rev to in order to downshift to next gear.....too high. Not recommended...

@1000 RPMs. Adding the 400 gives you 1400 RPMs ; That you can REV to for your downshift....

That’s the basic idea .....Think 400

 

For new drivers, look at your mph and use the above benchmark speed/ gear combinations.....easy peasy!

 

Do you have big feet ? Pictures maybe?

 

Just regular feet. Size 10. See how the throttle and brake are about an inch apart? Just put your foot on both of them. Push the brake with the left side, and control the throttle with the right. Just like heel-toeing, but with the sides of your foot instead of the ends of your foot.

 

I guess it's easier than it sounds

 

After a while you do it by ear.. hopefully. Staring at your Tach and Speedo to shift isn't really safe in the long run.

 

also helpful to keep in mind if you're anywhere over 20 mph basically any gear from 6th to 10th will let you in if the rpms are above 500, only problem is if you stick it too high and go to get back on the throttle it won't do anything except make noise, 8th would go in and might pull at 20 mph with an empty but loaded it would just grumble and sit there

 

Same here. This is why the peddles in real trucks are designed the way they are. They are low on the floor not hanging high from the dash. They are right next to, close and level with each other. All you have to do is slide over the toes or heel depending on your technique from one to the other without lifting the entire foot up and off needing to reposition it.