Posted 2013-08-05 5:22 PM (#153841 - in reply to #153764) Subject: RE: exhaust brake Powerstroke manual trans
Location: Colorado
The PAC-Brake is an excellent exhaust brake. And yes, it makes a big difference in what you can descend a steep hill with. It allows you to be safer, and to reduce wear and tear on your rig. And on yours specifically, it will probably make your rotors last longer, and warp and crack less! I'm in the Rocky Mtns, and haul and have hauled through the mountains all my life, both with pick-ups and trailers of all sizes, and tractor trailers.
The difference between an exhaust brake and a jake brake(Jacobs engine brake) is basically an exhaust brake restricts the air flowing out of the engineby plugging(mostly) the exhaust pipe. The jake brake actually opens the exhaust valve(s) at the top of the compression stroke, releasing the compressed air and absorbing the energy instead of allowing the compressed air to expand again and push the piston down. It basically turns your engine into an air compressor, the wheels are what drive it. Clear as mud? Hope this helps a little!
Posted 2013-08-05 11:01 PM (#153852 - in reply to #153764) Subject: RE: exhaust brake Powerstroke manual trans
Expert
Posts: 2453 Location: Northern Utah
These after market products only work on the older Ford Powerstrokes. 6.0L or 7.3L
B&D did have an exhaust brake for the 6.0L with automatic tranny. The one I have on my 2006 truck worked very well.
The new Ford 6.7L using the turbo to restrict exhaust flow and I find it works very well if I use it properly. It don't stop the truck, But it will hold speed on steep grades. 1st gear is 25mph, 2nd gear is 40 mph and 3rd gear is 60 mph. These speeds are all around 3000+ rpms. Which is where you get enough back pressure to produce some braking. At least with my 13,000 lbs trailer.
Posted 2013-08-06 10:59 PM (#153881 - in reply to #153869) Subject: RE: exhaust brake Powerstroke manual trans
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Posts: 2958 Location: North Carolina
Originally written by horsey1 on 2013-08-06 10:54 AM
Originally written by Terrye on 2013-08-06 12:42 PMIt is common knowledge that a diesel does not have the backpressure to slow you down like a gas engine. Good luck with your truck.Terry
Hmm. I thought it was related to compression ratio in the engine, of which a diesel is much, much higher.
While the diesel engine has much higher compression ratio, it is not working against any restriction... therefore a jake brake, inlet, or exhaust restrictor is needed. See my post on page one of this thread for an logical explanation.
Posted 2013-08-07 2:23 PM (#153886 - in reply to #153881) Subject: RE: exhaust brake Powerstroke manual trans
Location: Colorado
Originally written by hosspuller on 2013-08-06 10:59 PM
Originally written by horsey1 on 2013-08-06 10:54 AM
Originally written by Terrye on 2013-08-06 12:42 PMIt is common knowledge that a diesel does not have the backpressure to slow you down like a gas engine. Good luck with your truck.Terry
Hmm. I thought it was related to compression ratio in the engine, of which a diesel is much, much higher.
While the diesel engine has much higher compression ratio, it is not working against any restriction... therefore a jake brake, inlet, or exhaust restrictor is needed. See my post on page one of this thread for an logical explanation.
Exactly. And that is also why a jake works so well- you compress the air on the compression stroke- then at the top of the stroke, you release all that compressed air so it doesn't push the piston back down.
Posted 2013-08-07 10:33 PM (#153893 - in reply to #153764) Subject: RE: exhaust brake Powerstroke manual trans
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Posts: 5870 Location: western PA
All the years I've been driving, manual transmissions and automatics, gas and diesel, with or without trailers, I've always used lower gears to retard my passage down hills. Now I read where it didn't do any good and my efforts were for nought. Bugger
Posted 2013-08-09 11:19 AM (#153914 - in reply to #153893) Subject: RE: exhaust brake Powerstroke manual trans
Location: Colorado
Originally written by gard on 2013-08-07 10:33 PM
All the years I've been driving, manual transmissions and automatics, gas and diesel, with or without trailers, I've always used lower gears to retard my passage down hills. Now I read where it didn't do any good and my efforts were for nought. Bugger
Your efforts weren't for naught- probably saved you more than a few bucks over the years as far as replacing brakes! To say nothing of the gray hairs you didn't get cause you didn't scare yourself!
Posted 2013-08-11 9:28 AM (#153936 - in reply to #153914) Subject: RE: exhaust brake Powerstroke manual trans
Expert
Posts: 5870 Location: western PA
My comment was one of facetiousness. When I raced sports cars, I had to learn how to heel and toe downshift with rev matching. I've down shifted now for several decades, and saved myself many brake pads over that time as a result.