proper downshift

99.9% of the time, all thats required is the foot brake. jake brake is (imo) only needed for going down mountains. of course, unlike a 4 wheeler, you may find yourself in a jam if you make the decision to exit at the last second. a little planning goes a long way.

 

use the brake pedal as you would in an automatic, but also watch your rpms. once the rpms drop to around 12 you want to clutch-neutral, rev it up to 17rpm, clutch put it in. you can also skip a gear. like going from 8th to 6th by letting the rpms drop further to around 8 or 9. then... clutch neutral, rev it up to 17, clutch put it in.

 

In that vein, I've read/heard that instead of using brakes to slow down, downshift. But how do you get to the necessary speed for the gear you're downshifting to without braking? Or does that only work if you are already at a low speed?

 

downshifting lowers your speed and reduces your need for using the brakes, say like when your going downhill, or creeping in traffic. but you may need to use the brake to reduce your rpms to a point where you can downshift. but say your coming to a big uphill with a lot of weight you will already be losing speed from the climb and would not have to use the brake in that case. the main thing to realize is where the rpms are at.

 

and road speed

 

If your only doing 55-60, as you approach the exit, get off the throttle and let the jake bring you down to below 54, drop one gear and let the jake bring it down again. Now at the second down gear, use a little foot brake, gear down again...you should be at your 35 within 2 truck lengths. Keep it in gear until at a complete stop...at the moment of complete stop, it should slide right into your gear for start off.

Be mindful of other vehicles on the roadway as you prepare to decelerate....maintain close to highway speed until you begin your ramp exit....there is no reason to get down to the "advised exit speed" while still on the highway lane...signal well in advance (500 feet is the recommended distance...which is actually the distance the exit lane stripe begins).

 

put your tun signal on, brake (good and solid on the brake, it is actually bad for your brakes to ride them lightly. Just get in the habit of if you are going to brake, use them good and firm. This will help them stay properly adjusted, and also keep them from heat fading)

So brake as described until your rpm's are down to about 1200 rpm's, then downshift. you should click into the next gear about 1500-1600 rpm's. repeat process. use your jake if you have a heavy load and are not in a quiet zone. it only serves to save your brakes further. no reason not to use it where allowed.

 

Experience is going to be your best teacher; all drivers - and instructors - are human and have their own opinions about everything, and unfortunately some of them are wrong. Those of you new will find truck drivers are some of the most opinionated individuals in this world and also the most stubborn.

I use the engine brake a great deal, but as a courtesy keep in mind that e-braking with light gvw will slow your truck a good bit but drivers behind you won't see brake lights to know you are slowing and may get a surprise when your backside suddenly gets much closer (cursing may accompany their surprise) so maybe touch the brakes just to let them know if you slow in this manner.

My method for slowing for this situation would rest on these factors:
loaded, and if so, how heavy;
is the ramp approach uphill, level, or downhill and how long is the ramp.
doesn't hurt to be mindful of trucks behind you, if they could move over a lane to avoid slowing with you or not, but take care of your trucks needs before concern if someone has to slow behind you.

If heavy, begin slowing in advance of the exit by using the engine brake (keep in mind engine braking is more pronounced at higher rpm);
splittable trans (13- and 18-speeds) can take a 1/2 gear downshift with just a 200rpm drop, full gears about 4-500rpm.;
again, how heavy am I and how steep is the ramp - may continue to downshift or use service brakes, but keep the engine brake on full, but see how well I am slowing as to what I do (e-brake, downshift, service brakes and timing);
if you have an applied pressure gauge, I try to not use more than 15-20psi for stopping (earlier post about using short-but-hard brake app's is worthwhile, however).

My opinion only - take it as you will. You won't learn it all in school, and experience will be invaluable. Good luck!