Thor Forums

[powerboatr]

you have the VGT style on your engine


it does produce back pressure brake HP but not NEAR as much as a jake brake or engine brake


yes is will indicate a drop to 2 or 3 gear but WILL not downshift if road speed and resultant engine speed would exceed safe RPM


i have found on mine that its best to use it on exit ramps and the like and if your in hills or mountains, to stay OFF cruise
top the hill at the speed you desire for the downhill side



turn on exhaust brake and use your brake not aggressively but firmly to bring your speed down and then get off the brakes



if your rolling at 65 and just plan in exhaust brake to hold you back going down a grade...it will not have enough back pressure HP to do that. it will try, but again it will no downshift into a gear that would overspeed the engine, so it may engage and stay in 4th or 5 th until speed is such that a 3 rd or 2nd gear would let it do its job
it does rely on higher eng rpm to run at peak efficiency



HOWEVER a few tuscanys had the larger 425 hp cummins and it had a real engine brake,

what is your engine?