Anybody here have any experience w/ Ford SD 6.0 PSD?

[Diamondpilot]

I had to order my 2006 with 3.73's. All the dealers around here have on the lot is 4.10's. You see a lot of 3/4 tons with 3.73's but not many 1 tons around here. Don't let southern Indiana or any of Kentucky fool you, we have hills like that also. Most of my pulling though is 15,000 pounds or so at 70mph on the highway. Probably 10% of my heavy pulling is off the highway so the 3.73's are what I wanted for economy. I had a 4.10 truck once and it was really not needed although I did notice it got the same millage give or take in town or on the highway with that gear set.

Chris

 

[LarryRB]

I just tried the build a Ford from their site,, one ton, single rear wheel as I now have,, only option listed is the 373. Even though interstate 84 is almost outside my door, my machine towing is out local roads and thus the short but steep hills to pull,, Going backwards from 410 to 373 simply would not work for me

 

[GreatWhitehunter]

Larry, your way off base here. I had the choice when I bought mine of 4.10's
I opted for the 3.73 since it was my daily drive. As for hills I have had no issues loosing speed climbing the local hills. With 12k in tow I hardly know it's there unless it's bumpy. I tow both bp and gn. I average 17mpg both towing and unloaded. The only time I see a change in mpg is in winter when the blends change. I use the ford brand additive in winter and that seems to help. I also use mobil 1 full syn which quiets the engine in winter also.

Matt T.

 

[Dargo]

3:73 vs 4:30

With 3:73 my engine RPM is right at 2000 running 70 mph
With 4:30 my engine RPM is right at 2000 running 60 mph

 

[Diamondpilot]

All this talk about gear ratios makes me think of something. 2 years ago when my wife was looking for a 4 door 1/2 ton 4x4 I told her to go drive them all and narrow it down to 2 and I would go make a deal. Anyway she was torn between the Nissan Titan and the F-150. She came home with brochures for both and copies of the window stickers. The F-150 she wanted had 3.73's and after looking over the brochure it had 3.55 and 4.10 as options but 3.73's were fine for what we do.

The Nissan on the other hand had some weird gear like a 2.94 or something like that and a optional gear of something like a 3.23. I am making these numbers up but I am not far off. After doing some math with the tranny gear ratios and the tire sizes the standard gear was more like a 3.73 and the lower gear was more like a 4.10 when the tire hit the road.

So what I learned is the days of old when all trucks had 15" wheels and similar tranny's is past. With the new tranny's and larger wheels they can do lots to the end result where the rubber meets the road.

Chris

 

[Eagleview]

I always opt for a taller diff ratio (longer legs) as it's an easy matter to downshift a gear when needed for a hill . Theres always more flats than hills so why gear a truck for the hills instead of the flats where you can make use of engine torque and achieve better economy ?

 

[Dargo]

Theres always more flats than hills so why gear a truck for the hills instead of the flats where you can make use of engine torque and achieve better economy ?

To get that 20k load moving?

 

[Diamondpilot]

I pull 25,000# with my F-350 and 3.73's each spring and fall and never have a problem. This is a boat and I have to pull it out of the drink which is a good grade, I would guess 35 deg or more and never had a problem in my diesel trucks. I did have a 3/4 ton gas truck in 4 wheel low once that would not pull a 16,000# load up the ramp with out a little help from a Suburban.

I agree, its really not needed 99.9% of the time. There have been a few instances where I could have used it but then I have 4 wheel low to get it going and on flat ground.

Chris

 

[Dargo]

Since I bought my truck used, I didn't get a choice in ordering specific gear ratios. My 'old' 12v Cummins that is far from stock has enough grunt to roast all four rear tires no problem with 3:73 gears. My Ford is plenty peppy stock (as it should be with 4:30's!) but I have to admit that, after a decade of running 3:73's on the highway, it seems like the truck needs to shift again on the interstate. On the positive side though, I really think I am getting better fuel economy running in town. I really do; by almost 2 mpg. Which, of course, makes me wonder if I'm getting 2 mpg worse on the interstate. In all reality, it's probably not 2 mpg worse on the interstate but I do believe I do pay a bit of a penalty there with the lower gears.

And, as is true from the PM's I've received, I knew all about the 6.0 PSD from repair and breakdown statistics I get from some from some of the companies I do work for. I didn't go into this purchase completely blind. Statistics say that the '05, '06 and '07 6.0 engines are more reliable than the first year or so they were out. What I should have asked was about Ford's Torqueshift transmissions they began using in their SuperDuty trucks. When the 6.0 PSD is left stock, I'm really surprised at how few failures I've seen with the transmissions as compared to the transmissions behind the 7.3 engines.

 

[Builder]

And, as is true from the PM's I've received, I knew all about the 6.0 PSD from repair and breakdown statistics I get from some from some of the companies I do work for. I didn't go into this purchase completely blind. Statistics say that the '05, '06 and '07 6.0 engines are more reliable than the first year or so they were out. What I should have asked was about Ford's Torqueshift transmissions they began using in their SuperDuty trucks. When the 6.0 PSD is left stock, I'm really surprised at how few failures I've seen with the transmissions as compared to the transmissions behind the 7.3 engines.

No doubt the Torqslip is a step up from the 4R100 garbage I had to keep repairing, but it's no Aisin like in the Dodge and no Allison like in the GM.

You also have to remember the 6L is lower on power than the DMAX or Cummins and makes less power down low in the RPM range, so it's easier on transmissions.