Come on Rev, don't let your petty grievances with Steve put the spotlight on your own ignorance. There was nothing wrong with what Steve said. If you try to control a 78 or 79K truck down a 7% grade with the brakes you won't have any when you get to the bottom. You gear down, then you use the jakes, then you add the engine fan if you need it. You use all the tools available to you BEFORE you use the brakes.

My cousin taught me to drive and he retired with over two million miles of driving without one at fault accident. He told me three things that really stuck with me over the years. Stay away from truck stops, GET IT IN WRITING, and use the brakes only when all other avenues have been explored. Pretty good advice and all three have kept me out of trouble.

Excuse me?

That is poor advice, plain and simple. If you feel it necessary to use your engine fan to slow your truck, then chances are you're going too fast in the first place. The fan is not a tool for slowing the engine - it is a tool for cooling it. :roll:

I've driven plenty of trucks with no jake brake available to use down heavy grades, maxxed out at 80K. I've never smoked a brake doing it either, because I took the steps to prevent it before I ever began going down the grade.

Good for him. Now explain how playing with switches is safer than pushing on the brake pedal. The proper way to go down a hill is to:

#1. Slow down at the top
#2. Gear down
#3. Set your jake
#4. Use your brakes to maintain your speed.

If you do the first three, then the fourth should only have to be used every once in a while anyway.

Although if you are wanting to put excess strain on your fan belt, then by all means pretend it's an engine brake. :lol:

Besides - using your engine fan to slow the truck isn't going to give you hardly any slowing power anyway.

Rev hate to do this to you AGAIN the avarage HP draw of a Air operated fan when it engages in in the area of 60HP. That is right it takes 60 ponies to spin that fan around now I do not know about you but to me that is alot of braking power to add o keep me slowed down. One company I drove for even set it up so the fan came on when the jakes came on full so that we had EVERY ONCE OF ENGINE BRAKES WE COULD GET coming down some mountians. Millis transfer to this day still sets them up that way so does Henderson Trucking. Henderson runs Detriots and the other runs Cats maybe it is your PROTOTYPE CUMAPART that can not handle the extra pressure.

I probably have no right to comment on this since I am as green as they come being that I just got my CDL. But while in CDL school one of our topics was "extreme & mountain driving" and it was taught to us EXACTLY as Rev. stated in those EXACT steps. The first two steps being the most important. The 4th step should be used to bring your speed down below 5mph of your safe speed and then repeated as needed. Just my 1 1/2 cents worth

:roll:

Show me where that 60 hp number comes from. If that were the case, and your engine fan came on while climbing a hill, you'd lose some major speed and torque.

Who has a prototype engine? :roll:

That's exactly right. If you take a mountain grade properly at the beginning, then your brakes should only need to be used for correction purposes. Depending upon the grade, and my gross weight, I will go as much as 10 mph below my safe speed just to give myself that much more of a buffer. Most times, I never even have to touch my brakes, and if I do, it's only to drop one or two mph, and then I can let off them again. No engine fan in the equation at all. :lol:

I would love to know how much strain using your engine fan as a brake puts on the belts, since I doubt they are designed for torquing the engine down to a correct speed.

FWIW, engine management computers can be programmed to engage the engine fan automatically when the engine brake is on. I don't think it's a 60 hp draw, I seem to recall the number being around 15-25hp at the most, though it's possible it could be higher since the fan speed probably increases the HP draw exponentially (descending a hill at 2100 rpm with the fan on will create more "power robbing" braking HP than climbing a hill at a lower RPM with the engine fan on because the fan isn't spinning as fast.)

You stated your truck was s;peced like a prototype in one of your threads. Besides the ISX based CUMAPART has one of the worst designed engine brakes ever. Sorry drove an early verizon on it and at 79K coming down Parlay going into SLC on max it could not hold my speed checked. My 60 Series had not one problem at 80K however and the trucks were speced the same EXECPT FOR THE MOTOR. For Cummions to call the ISX an improvment over the N-14 is stupid. The N-14 was easier than heck to work on every mechanic in the world nderstod it since all it was the next gen Small/Big Cam series with Electronics on it. Tell me this Rev ever help your bosses save 1500 lbs in your companies trucks while improving driver comfort productivity and the company bottom line all at the same time I highly doubt it.

DING DING DING

My truck is a prototype. The engine isn't. I've driven some Cummins that had poor engine brakes, but not all do.


?

I was a member of the DRIVERS advisory board at one company and when I started there we had very heavy trucks and they sucked if you were a driver and our turnover was skyhigh. The boss came to us and asked us to see what we could do to improve the trucks from a drivers point of view. We had to keep the cost of each trucks improvements under 4K total. 1st we added 10 alloy wheels saving 500 lbs then removed the side skirts saved us another 200 lbs then added real fridge and a microwave to all the trucks added 80 but we will still ahead. Then we changed the springs to compsites on the front end saved 180 lbs there we then lowered full capcity since we didnot use all we had anyway by 20 gallons total tank weight was 100 lbs fuel weight was 150 lbs. then we used an alloy driveshaft and hubs for the rest. In the cab we installed top of the line seats with massage and thick like 8 inch thick mattress for the drivers in the bnks costs were at 3K total per truck. We also increased HP from 400 to 470 without having to beefup at all the drivelines.