2020 Freightliner vs 3500 GMC Dually at the Ike

4x4ord wrote:

Me Again wrote:

4x4ord wrote:
They praise the performance of the engine brake on the Freightliner over the performance of the exhaust brake on the GMC, however, if more weight had been loaded into the trailer the Duramax would have held 50 mph yet the Freightliner would have required additional brake applications. Comparing two trucks on one hill with only one weight in tow doesn't really offer an honest comparison. I'm having trouble understanding why the GM slowed down as much as it did going up the hill ..... something doesn't add up. Even back in 2015 (with 396 HP and 765 lb ft) the Duramax towed 19000 lbs up the Ike in just under 10 minutes. link

I don't think your statement on the Freightliner is correct. The cruise control was holding it at 50 MPH, most likely had a lot more anchor chain in the chain locker. RAM has this feature also when the EB is in auto. I do not use it because it does not brake until about 3-4 MPH above the CC speed.

I think the new GMs likely adjust the exhaust brake in auto as does the Ram and Ford. I believe in the test they had the GM exhaust brake turned to "on" which makes me think auto wasn't available in 2017. With the Freightliner Mr Truck said he didn"t have the cruise set. He said the engine brake could be set at 3 or 6 and he had it set at 6. So the Cummins was braking all it could without downshifting.

I looked at it again, and yes he did say that he was not on CC. My bad! He did however say that the engine brake was holding the truck in 4 gear or lower and holding the 50 MPH speed, so it had to be modulating the engine brake to maintain 50 MPH as the grade changes.