Understanding downshifting

I use RPM up shifting and MPH down shifting.
Many "instuctors" aren't worth a hoot.

 

each gear has a MPH that it tops out at, if you're going 55 and try to stick it in 5th, it won't go in, the engine can't spin fast enough for that gear.

I got taught to quick add the numbers of the MPH for an idea of what gear to shoot for (in a 10 speed) if i'm bringing it down off the freeway...

35mph = 8 = 8th gear
25mph = 7 = 7th gear
15mph = 6 = 6th gear

if your truck isn't RPM limited and you can take it up past 1500rpm, you can make a note of each gear to see how much MPH it stops at at 2000rpm, then you know if you're anywhere below that speed, you can grab that gear and it will go in

 

Pay attention to RPMs while upshifting, note the amount the rpm changes between gears. When downshifting, rev it up the same amount, works both ways. On a 10 spd for instance,lug it down to say 1100, then take it out of gear, and rev it up to around 1450-1500, and drop it in the next lower gear. Roughly speaking. Exact RPMs depends on the spread between gears. It helps to listen to the engine revving. Soon you’ll get the hang of it and be able to shift by ear,

 

You in a 10 speed? 400 rpm between gears. Look at the tach not the Speedo. When on the low side your speed might drop faster so sometimes it's not gonna be exactly 400

 

Use your ears.

 

I never look at speed. When I hit 1600-1700 I upshift, when I get down to 1100-1200 I downshift.

 

I use RPMs. Upshifting it's out at 1,600, in at 1,200. I run the engine brake down to 1,200 and rev to 16 to downshift. Of course every engine/trans pair reacts differently, you just have to learn your truck. Research the torque/HP curves of your engine and find the happy medium between both to figure out your best shift point