Recently on a cross country trip, 2017 Ford f250 6.2 liter, I encountered a long uphill grade. Not terribly steep, just long. The transmission, even in tow haul, shifted frequently and, since I had to keep my foot in gas pedal, shifted hard several times into lower gears. Quite often it shifted hard all the way down to 2nd gear just to maintain a speed of about 35. Again, this wasn't a very steep grade. Also, only pulling 8k trailer (loaded). I wasn't really pleased with the performance of the truck on any grade, but that's another story.So here's my concern. After the long hill, I stopped for gas. I could smell gear oil (like differential oil). I looked underneath and there was nothing leaking. Checked the tranny fluid and it was nice and pink. The trans temp, according to the gauge, was only a couple degrees above normal (203-204).I didn't think things were being overworked, but maybe so.Anyone have any thoughts as to what would cause the smell?Also, took it to the dealer and they couldn't find anything wrong.

The driver is the problem! You need to adjust your driving habits for your truck. You need to slow down going up the hills, find which gear and engine RPMs that it likes.Depending on hill, you could be in second or third gear at about 3000 RPMs in many rigs. Your engine and transmission gear lube got hot. It should be OK.

When transmission starting shifting gears back/forth.....STOP letting it do thatDrop down a gear and hold that until you made top of grade."Hunting" generates excessive heat...trans cooler controlled oil return temp but tranny oil was getting worked real hard

Agree with above post. We pull 10000 pounds with 6.2 and 4.30 axle. I seldom use drive and tow haul in hilly terrain. Put it in M and control shifts yourself. I anticipate the hill, shift down before it starts to struggle and then use a gear that keeps RPM at about 3500 to 4000 RPM and 45 to 50 MPH using only moderate throttle. I never put my foot to floor and am not worried if I lose speed on hills. If that so concerned me I would have a diesel, so what if I get to top of hill a minute later than a diesel would. The 6.2 pulls hard in the mid range and I have seldom felt the need to run it much beyond 4000, but if you do it will really pull hard, but why flog it, its not a sin to slow down a bit on a hill!

Best to keep it in a lower gear and hold the rpm where you can maintain an acceptable speed. Expect it to need high rpm to tow up hill, that's normal.

Since it's a new truck, I wouldn't worry much about the burning oil smells. There's lots of surfaces that come with a light oil film from the factory, and it just doesn't burn off until the first hard pull.And yes to what the others are saying. Manually downshift to hold a lower gear, and be patient to the grade. If you were at high elevation, or the grade was above 7%, 35 MPH isn't unexpected.

Any drivetrain gurus out there? | Good Sam Community

jkwilson
Explorer III
Oct 06, 2017
Chuck_thehammer wrote:
I like to keep the 6.2L between 3,500 and 4,000 rpm's going up Hills...

manual mode and shift to keep said rpm's.

I carry 1,500 pounds in bed of truck AND tow a trailer over 9,000 pounds.
and my 6.2L has 153,000 miles, its a 2012 F 250 XL....SCLB. with 3.73 gears.

the engine is overhead camshaft and designed to spin lots of rpm's.

also the Ford 6.2L is 'Fly by wire'.. so if you think the throttle is at half.. its NOT...

This^

You need RPMs to generate power in a gas engine, and it's nothing to turn 4000RPM when hauling a load with one of these engines. I always imagine the scene where Belushi chugs the bottle of Jack Daniels in Animal House when I'm pulling a long hill in mine.

But I'd also be checking the differential oil.
tinstartrvlr
Explorer
Oct 06, 2017
Been fulltiming for several years with thousands of miles towing with a trailer, so pretty familiar with grades and the whole dynamic. The weight of the trailer is scale weight. 3.73 gears. Elevation was probably around 2-2.5K feet; not so high as to seriously sap horsepower IMO.

Anyway, it was the smell that concerned me; if I was climbing a 6 percent grade at 5k rpm, I might expect things to get hot and start smelling. Don't think I hit 5k the whole trip. But even on the steep grades, the engine/trans temps barely went up. It was just this one incident, and the smell has not returned.

Didn't know diffs had a breather, so that confirms my thoughts about which smell it was.

It just didn't seem this particular situation was one that would cause things to get so hot.

I tend to agree with the performance problem. Maybe it was just some bad gas.....

Not going to worry about it since other than a little more slop in the drivetrain, everything seems to be ok.

Thanks again everyone for the input.
rhagfo
Explorer III
Oct 06, 2017
No way a 6.2 should be pulled down to 35 pulling 8,000# on a 3% grade!!
Either the driver is afraid to let it rev, or something is wrong with the engine or drive train.
It is not a diesel or EcoBoost it delivers max HP and Torque at high revs 4,000+.
goducks10
Explorer
Oct 06, 2017
Sounds like you were doing an Ike tunnel road test. Those guys just floor it and make the truck do it's thing. Problem is thats not really how these trucks are designed to run. I found that even with my CTD that I don't always maintain the speed limit up hills. I can but all I'm doing is running temps up. I found that it's easier and way more relaxing to find the gear and speed that has the pedal partially down. No flooring it or assuming a certain speed is needed. I just go by pedal pressure. My temps stay in the normal range and my mpgs are better.
What you probably experiencing when pressing the pedal to the metal is the truck will speed up to it's max then as gravity takes over it slows down and drops gears. Rinse repeat, rinse repeat. Just find the sweet spot in the gear that causes the least amount of shifting.
Also with 8000 lbs and guessing 3.73 you're probably pushing it a bit up longer hills. Had you had 4.30 gears you would've been able to maintain a higher speed without shifting up and down.
Retired_JSO
Explorer
Oct 06, 2017
I leave my 6.2 in auto tow haul, lock out 6th on flat roads. Up grades, long or short I shift down with minus button sometimes to 2nd. Let the engine turn as high as 5,000 rpms if needed.
Dave_H_M
Explorer II
Oct 06, 2017
:h not terribly steep.

I control my 6.2 like Chuck on the long pulls. however i just lock out the upper gears as needed instead of doing the "M" thing.
valhalla360
Navigator
Oct 06, 2017
Where is this grade at? I'm wondering if you just think it's 3% and it's really 5-6%.

Also, is the 8000lb the empty weight or actual scale weight loaded.

If it really was a 3% grade and the trailer is really 8000lb, it sounds like there is something wrong. The smell may be harmless but sounds like the performance is off from what I would expect.
mowermech
Explorer
Oct 06, 2017
I had that gear-hunting problem towing a 7X14 box trailer behind a Dodge Ram 1500, with the 360 CID V8, auto transmission.
I sold the truck, and got the one in my sig. No more towing problems. I can hook that same trailer, with two Kawasaki Brute Force 750 ATVs aboard, to the Cummins powered truck, and climb any grade in fourth gear, maybe even fifth.
The driving experience is SOOOO much nicer!
Grit_dog
Navigator
Oct 06, 2017
Correct 3% ain't much and if you could hold speed in 3rd gear down to like 50 mph without a downshift that's about all I'd expect though.
Probably got a little deep into the pedal and a little slow and she kicked into 2nd trying to gain speed based on throttle position.

Overall, it's a new truck. Run it like a rental, IMO. If there's something wrong I'd rather have it happen under warranty and if there isn't, then you're not hurting anything to put your foot in it.

Maybe also just a bit of over expectation for the 6.2 as well. Which gears? Mine were 3.73s and I could see deeper gears helping a good amount.
Hybridhunter
Explorer
Oct 05, 2017
Grit dog wrote:
How much slower than 35 mph would you like the guy to go? Those types of reccomendations come from folks that irk the majority of drivers by putzing along as slow as humanly possible, imo.
As much as some would like to think, new vehicles still require or at least need some intelligent/qualified input from the driver when tackling more than a Sunday crooze with no load.
First, yes your truck was likely giving all she had. 35mph with an 8000lb wind sail up hill is not out of the question to dog down a gasser. My 6.2s were in 2nd at close to redline to maintain 50mph up 8% grades at moderately low altitude with less trailer than you were pulling. They wouldn't hold 3rd gear.
....snip.

No reason a new 6.2 should struggle on a 3% grade, imo.

And you are right on with the "putzing along" statement. I say drive roughly the same speed towing or not, new vehicles can do it safely, and I don't like being the slowpoke.