Filters were just changed about 2,000 miles back. It pulls higher rpms at lower speeds going through the gears so filter should have nothing to do with it.

 

I know that hill, and would be thrilled to pull it @ 65mph.

The Cheby 2500 was tough to keep it 50-55 especially when you hit the 1st and 3rd part of the climb. The middle part was where I could get some of my speed back to get it up the 3rd section that tops out @ the scenic overlook.

 

I had an 04 gmc 2500 DMax and a 40' 5th wheel and pulled the hill at about 55 could have gone faster but the truck would heat up a little bit so i didn't push it. My 11 ecoboost would pull this hill with my current 8000 lb trailer at 70 with no problem and I could accelerate. This truck has almost 300 ft lbs of torque more than my EB. It should be able to accelerate not just maintain 65mph. Just seems wrong to me.

FYI if you go up there and dry camp, the forest service has cut the dispersed camping areas by over 70 percent and they are issuing warnings now and will be ticketing in the future. The tree huggers want to completely shut down access to the forest and probably will within the next few years!

Thanks

 

That's funny mine was an 04 also...but it was the gasser. And I could also get a bit more out it but something about screaming along at 5000 RPM or more didn't seem right.

And that's a shame about the dry camping up there, have not heard that. But I have only camped in Flag once (Mormon Lake), usually I am just passsing through on my way to Lake Powell.

 

I had a simular thing happen in Newfoundland. It was dirty diesel that fouled my fuel filters and limited flow. Flow was fine without load because demand was less.

 

Ikbrow1 that is what I was thinking.

Shelby could your problem be bad fuel. Similar to this problem: https://www.ford-trucks.com/forums/1...d-mileage.html

Maybe? Just a thought, try adding some conditioner and see if it helps.

 

Honestly, if ou are comparing to a duramax, this truck MIGHT feel slow. Technically we do have the slowest and marginally less powered trucks as compared to the others.

And the ecoboost is very powerful. A strong turbo charged gasser is hard to beat. But general every day towing is unbelievably pleasant with the 6.7. I'm not ignorant enough to blindly assume that our diesels are the best at everything all the time no matter what. All engines/trucks have their plus sides.

I will stand by this though, for the way I use my truck, a diesel is the best choice and outperforms all other engines in terms of comfort, performance, and value.

I hope your truck is ok and you figure out what's going on.

 

I will check the fuel but don't think there is any possibilty that it could work at low speed and not at high speed. When I accelerate hard towing the trailer the motore goes up and down on rpm as the truck goes through the gears so it is running very well at higher rpms just lower speed.

I had a governer on the f150 think it was around 90-95 can't remember. I heard the 250 has a lower mark for that. Maybe 80-85 this could be kicking in.

 

Same here. When pulling that grade with my '99 F250, I have to pull down to second gear and back off the throttle to hover around 2600 RPM (which is about 45 mph) until I get to the top. If I leave it in drive, it will shift to third but then my EGTs get pretty high and the coolant temp climbs. I am still tugging with old technology though....at 24,800 lbs gross, it would be a miracle to see 65 mph going up that pass.

 

This is stupid of me, I know, , but I crused at 95+mph with a little 2k trailer this past weekend. Maybe it is governed at 100mph.

 

I am sure the truck handled it OK, but the poor tires on that trailer...

Now let me guess where your handle came from

I believe I read that the governor is 100 on these trucks.

 

In the past it has been 96. I don't know what my '11 is limited too, I think we can all assume it's somewhere in there.

 

X2 on 95-96

 

So maybe Shelby's is governed at 65?

Sorry, couldn't resist.

 

Why did you sell the Ecoboost?