Hello,

I have to admit, I'm new to driving a MANUAL transmission with a horse trailer...Every time I drove my manual car, I have the habit of shifting into neutral and braking to stop (no matter how fast I was going)...So, needless to say, I have the same habit with my new Manual Truck (for reference, it's a 6 speed 1 Ton Dodge Diesel..I love it!  And don't want to ruin it).  I am told not to shift to neutral, but to downship 1, maybe even 2 gears at a time to let the engine help stop me.  A separate matter is that it has a jake brake, and I'm not sure when to use that...I'm told mainly for hills...but the dealer told me to use it whenever I tow, though that doesn't make sense to me because I tried it and I cannot coast (on a freeway or highway) without the jake brake being engaged...So, I guess there are two questions here....Downshifting, vs putting the truck in neutral to shift, and when to use the jake brake....If you can understand my ramblings, please answer me as my horses mean the world to me and I want to do what's safe...But I also want to do what's best for my truck...

Thanks a lot!

Kari Reilly

Somebody is bound to have more closely related experience than mine, but since nobody has answered you yet I'll throw in my 2 cents worth.  My F350 is an automatic transmission, but I grew up on a farm and put myself through college driving grain trucks with 10 gear, two speed transmissions.  Hauling loaded was almost always dowhill, did ALOT of downshifting under load.

When you would normally shift into neutral with your car (when you know you are going to stop, like when the light ahead turns yellow), you would shift into a lower gear.  Gradually take your foot off the clutch after shifting into a lower gear to let int reingage at the higher RPM's, and continue downshifting this way until you are in your lowest gear or stopped.  You will have to learn the particular gearing of your truck to know if you can shift down two gears at once or not.  I don't shift down more than one gear at a time, nor did I with trucks (I drive a 6 speed manual transmission car currently).  You will eventually get to know at what RPM in the higher gear you can shift down to a lower gear and have it not rev too high in the lower gear.  It may take some braking before shifting if your RPM's are too high to shift down. 

I hope that makes sense.  Hard to explain without actually being there.  As far as the jake brake, I have no idea.  I believe the jake brake is a relatively new feature on the Dodge, I would ask the dealer or find one of those Dodge truck forums (I only know of the Ford one).  Have fun with your new truck! 

Coasting in neutral while towing is NOT a safe thing to do...if you have to stop you are using ALL BRAKES...you also run the danger of overreving when you select a gear after coasting or jerking, if you choose too low a gear for the road speed when you let out the clutch...This can be very bad when you have a heavy trailer pushing you...

The very last thing you do before you stop is put in the clutch...always use your driveline to help you slow down...that is unless you own a brake shop...

Your Exhaust Brake, if it is engaged, will operate when you decelerate...another brake saver...

That being said...assuming you have the Jacobs exhaust brake, approved by Cummins and Dodge as a dealer-installed option. This should, if used correctly, eliminate the possibility of engine damage or discrepancies with related powertrain warranty claims. The magic number is 3200 rpm; let's call it the Jacobs redline. Exhaust brakes do their best work at higher engine speeds, but exceeding the 3200-rpm threshold during deceleration may produce dangerously high levels of backpressure, similar to how accelerating past your truck's redline exceeds the engine's designed capabilities, and therefore increases the risk of engine damage. Most exhaust brakes don't allow the butterfly to close all the way, or they incorporate a calibrated orifice to avoid a complete blockage of the exhaust system. This prevents backpressure from surpassing the engine's limitations--even if the exhaust brake fails and is stuck closed. But again, engine safety goes out the window if you blow by that Jacobs redline. An exhaust brake can be a valuable asset and a reliable component for commercial and light-duty diesel-truck applications.

Here's a question...............

Why would you want to tow with the cruise control on anyway? I have never done that, and was always taught never tow anything with cruise control. I would rather have full control of my rig.

Yes, you will want to downshift with the manual while towing.  That is what helps you get the full benefit out of the exhaust brake.  The increased revs will increase the back pressure hence more engine braking power.  The trick with downshifting is to match your rpm with the vehicle speed, and the gear you are selecting. You must select the appropriate gear.  If you select a gear that is to low you will over rev the engine which is bad.  While first starting out just downshift one gear at a time.  Say 6th to 5th to 4th.  It takes practice.  I would suggest you practice this unloaded.  You will want to be very smooth.  That is the secret.  Go out and try doing this unloaded on a back road with no traffic.  Try to slow down without touching the brakes. Just by downshifting. I used to teach folks in the military to drive a manual stick  with deuce 1/2's military trucks.  I would make them start out with just the clutch and no go pedal. Once they got that down then I would let them use the go pedal. I also taught them to downshift.  Practice, Practice, Practice. If you don't feel comfortable doing it hopefully you have a friend that drives a big truck for a living. He will be able to show you how it is done properly.

I almost forgot.  Turn the exhaust brake off when you first start practicing slowing down by downshifting. Once you get the hang of it turn it on. Remember, the more RPMS the motor is turning the more engine braking you will have with the exhaust brake on. It will be fun and can be a life saver while towing with the extra braking power.

Yes, you can use an exhaust brake on a Dodge/Cummins auto with the cruise set.  It will automaticaly apply the exhaust brake to keep you at the set speed of the cruise control. Very nice.

Wow,

Thank you all very much for all of your replies...That helps me out immensly.  Just one question.  Should I always select the jake break option when I'm towing...or only down hills (the reason I ask, is because every time I take my foot of the gas, the jake brake comes on and slows me down...even if I'm just trying to coast).  I haven't tried it with cruise control yet though.

Thanks again!

Kari

Again...Thank you very much.  You've been very helpful.  I've got my husband telling me one thing, and other horse folks telling me another, so it's nice to get consistency from you guys.  I appreciate the help!!

Kari

Not if they're disk all the way around and the anti-lock units have to be replaced as well...an individual up here in VT got a $2500 bill for discs, rotors and the antilock mechs and labor on a 3/4 ton Chevy...

I had an automatic trans for my Dodge 1 ton rebuilt by AAMCO for <$2000...and that included adding a transmission cooler and trans temp gauge...

Actually,

That is my husband's argument...That brakes are cheaper to replace than a transmission...But is downshifting to a stop really THAT bad on your transmission?  It seems these trucks should be meant to handle that if that's how your supposed to drive???

With a Dodge/Cummins they are approved from the factory and are dealer options to have an exhaust brake installed. All the new ones come from the factory with an exhaust brake (07.5 Trucks). The problem is if you get to the bottom of the hill and have no brakes what real difference does it make.

If done properly it is not bad at all on the transmission.  Mind you that anyone can tear something up no matter how good it is built. That is why I said go out and practice.  Down shifting done properly with that exhaust brake can slap you forward into the seatbelt. That is also why I said to practice.  You don't want to throw your horses into the slant dividers. Well, maybe in an emergency to keep from hitting someone and that would be much worse.