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mkguitar's avatar
mkguitar
Explorer
Aug 22, 2015

Diesel Sprinter downshifting to slow question ?

Question for you Guys and Gals with Diesels.

what is the result if you downshift on a grade- how well does the motor compression slow your B ?


I have a chev based b with the 6.0 liter gas and on 6% grades 3rd gear will hold to about 55 MPH, 2nd will hold to about 42
downshifting to control speed keeps my brakes cool should I need them.

Just wondering.

In a previous life, I drove lots of large diesels, but we had exhaust brakes ("jake").
I saw a pretty wacky sprinter driver about set his brakes on fire the other day.

Mike
Class B
  • obgraham's avatar
    obgraham
    Explorer
    Aug 25, 2015
    I can't say the compression braking on my 6 cylinder Sprinter is anything like it was on my prior Cat Diesel pusher. However, I like the kickdown shifter, use it on nearly all downgrades. You get some braking, but mostly it decreases the amount of speed buildup. Then if you need to, brake hard and short, as others say.

    I like the way this rig takes the mountain driving, both going up and down. Chinook and Cayeuse passes east of Mt Rainier were a pleasure to drive this past week.
  • georgelesley's avatar
    georgelesley
    Explorer
    Aug 24, 2015
    midnightsadie wrote:
    X2, works for us.


    X3. It took the wife awhile to learn a short hart jab on the brakes is better than a long slow tentative brake application. Now she drives the Rockies like a pro.
  • Fastpaddler's avatar
    Fastpaddler
    Explorer
    Aug 24, 2015
    For the T1N1 5 cylinder diesel on my rv I often keep the txn out of 5th and in 4th on steep winding roads, downshifting to 3rd as needed. I keep revs below 3500 and more like 3000 for the 5 cylinder. Compression braking isn't a big benefit. Sprinter brakes on mine are quite good and don't fade much even under heavy use, which is seldom. It is essentially a truck so I drive it like one, including downshifting out of o/d 5th on steep incline hills.
  • bobojay5's avatar
    bobojay5
    Explorer
    Aug 23, 2015
    I assume you are referring to the Sprinter diesel? Diesels without an exhaust brake don't have a whole lot of "drag" when downshifted. The brakes cannot be installed at least on the 2008 on up V6 Sprinter, or the newer 4 cyl Sprinter I'd bet because of all the emissions equipment.
    We haven't had any issues with either of the Sprinters we've owned in the mountains. Just run in 3rd gear, keep the rpm's below 4k, (the V6), and brake hard for short periods to keep the heat down
  • Winnebago_Bob's avatar
    Winnebago_Bob
    Explorer
    Aug 23, 2015
    Diesels without a decent exhaust brake offer little in the for of engine braking.

    WITH an exhaust brake they make gas engines look silly.

    While not a Class B - my Dodge Cummins with exhaust brake and tow haul mode makes moving our 21,000 pound load almost brainless.

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