Driving in hills per Advanced RV newsletter

[Rok]

Here is an article sent to me via e-mail from Advanced RV in their online newsletter. I think it is good advice, but I have a couple of questions about it.

First, here is the link: http://www.advanced-rv.com/best-practic ... dium=email

I am probably a bit more conservative than most, but for a Sprinter, is it really O.K. to travel at 90% of the redline when going down hills? I think we try to keep it at 80% or less.

Also, is it really true that you can't downshift if it would cause your engine to overrev? Mike, the owner of Advanced, is a good guy, and he undoubtedly knows what he is writing about, but I think the article was written by someone else and was targeted to the Class A market.

.........Rocky

[Davydd]

The article appears fairly accurate for a Sprinter B. As far as going 80 to 90% of redline I sense it more from listening to the engine than watching the gauge. You just know. I've driven most of the major passes in Colorado and the I-70 stretch mentioned in the article in two different Sprinters (5 and 6 cyl.) and have had no real concerns of over stressing the engine. You can downshift and most of the time not need to touch the breaks.

I see he was driving the 4 cylinder in the mountains. How it performed was still rather vague in details.

[booster]

Originally Posted by Rok

Here is an article sent to me via e-mail from Advanced RV in their online newsletter. I think it is good advice, but I have a couple of questions about it.

First, here is the link: http://www.advanced-rv.com/best-practic ... dium=email

I am probably a bit more conservative than most, but for a Sprinter, is it really O.K. to travel at 90% of the redline when going down hills? I think we try to keep it at 80% or less.

Also, is it really true that you can't downshift if it would cause your engine to overrev? Mike, the owner of Advanced, is a good guy, and he undoubtedly knows what he is writing about, but I think the article was written by someone else and was targeted to the Class A market.

.........Rocky

90% of redline seems high to me also, but not as much on a Sprinter as on the gassers. I don't know what the redline on the diesel is but it probably isn't above 4500 rpm-90% @ about 4000rpm. I think the Pentastar V6 redlines at 6400rpm which would be over 5700 at 90%. RPM related forces go up very quickly with engine speed, so that is a big difference. I would think lower rpm is better going downhill, and uphill, when it comes to engine wear.

[Fastpaddler1]

Like Davydd suggests, it is really a non-issue. You should always keep tabs on engine rpm.Diesels are not big revvers and one should downshift to use engine breaking when necessary and thereby save the brakes. I do that on my big Bimmer 5 series. If the diesel on my I-5 gets up to 4 grand it will let you know to upshift because you get valve float after that anyway if you are manually shifting. If in automatic it shifts itself up at around 3 1/2 grand. I guess there are people who dont know about downshifting and using engine compression to save your drivtrain.