My 2008 F450 XLT 4x4 6.4L

   / My 2008 F450 XLT 4x4 6.4L #1  

brain55

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Jan 19, 2008
Messages
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Location
Brentwood, CA
Here is my initial review after the first 330 miles. I have had this truck 3 full days now. My first fill up on Friday cost $143, it was down to an 1/8 of a tank and has a 37 gallon tank. The mileage computer says I'm getting 12.7 mpg, I will confirm this on the next fill up. Not the 15 mpg that some people had predicted. This is mixed driving city/highway. Still better than my 8.1L that got around 9 mpg mixed.

This truck rides like a truck. It is not uncomfortable, it is just firm and you feel every bump. The only 2 trucks I have to compare against it are my 2001 GMC Sierra K3500 and my buddy's F350 King Ranch SRW 4x4 with a 6.0 that I have been using the last couple of months when I really needed it. It rides rougher than either of those.

I am still waiting for my gooseneck hitch to come in to report on how it tows.

The Oasis report said it has 4.30 gears, at 60 mph it spins 2000 rpm which is about the same as my GMC, of course it had the 8.1L and not a diesel. This truck also seems to make a lot of boost, more than what I noticed with the F350 I have been using. I cross some hills everyday, and going up the hill unloaded it will make 30 psi boost, the only time my buddy's 6.0 makes that much boost is with the trailer hooked to it. I'm assuming that is a result of the twin turbos on my truck. His truck also has lower numeric gears.

I am also curious about the licensing and insurance. I think it will have to be registered as commercial vehicle and insured accordingly. It having a factory pick-up bed on it might help but I'm not counting on it.

I'm also starting to plan its first maintenance at 45,000 miles, it has 41,600 now. Everything I have read says to make sure the engine oil gets changed every 5000 miles. I will change both fuel filters at every oil change, even though the manual says they can go 10,000 miles. I also change transmission fluid every 15,000 instead of 30,000. Since this is my first service and I'm doing everything else, I'm going to do the differential fluids and transfer case too so everything is on the same schedule. In the grand scheme of things, fluids and filters are cheap.

I will check back later in the week with some more pictures and a towing update.

Brian
 
   / My 2008 F450 XLT 4x4 6.4L #2  
Almost 13MPG isn't too bad on a monster like that...I'd be kinda happy with that.

As far as insurance....You're kinda are commercial right?....This truck is your office for the most part. The plates will probably hurt, but the rest shouldn't be that much worse than your last truck. Insure for the risk. From what you've said about what's in your trailer and the weight of it, I'd look into an umbrella policy. I just did that and it's very reasonable.

I'm not commercial, but my insurance actually went down on my '11 GMC compared to my '04 GMC..Go figure.
 
   / My 2008 F450 XLT 4x4 6.4L #3  
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   / My 2008 F450 XLT 4x4 6.4L #4  
Glad to hear the truck has 4.30's instead of the 4.88's. You're truck is getting about the same mileage as my F-450. I'm averaging about 12.5, if I keep my speed down to 65 or less I can get close to 13. Not good but it is a heavy truck. You'll forget about the firm ride as soon as you hook a trailer to it, the F-450 pickup is a supreme towing machine. Keep the oil changed and don't idle for long periods and the 6.4 will be a good engine.
 
   / My 2008 F450 XLT 4x4 6.4L #5  
Glad to see its working out for you. Like others said, once you hook that trailer to it you will see where it shines.

Chris
 
   / My 2008 F450 XLT 4x4 6.4L #6  
I've been in old F-450's, they are certainly sprung to handle the load rating on that rear axle for sure. Not a pickup for daily driving if you don't need to load it down.
 
   / My 2008 F450 XLT 4x4 6.4L #8  
Mileage doesn't sound bad at all for that truck. It's good that you plan on a short oil change interval, that seems to be the real killer of any newer diesel engine.

Good luck with the truck! :thumbsup:
 
   / My 2008 F450 XLT 4x4 6.4L #9  
Mileage doesn't sound bad at all for that truck. It's good that you plan on a short oil change interval, that seems to be the real killer of any newer diesel engine.

Good luck with the truck! :thumbsup:

I completely agree. With that gear ratio, and the weight of that hauling machine, I think those fuel economy numbers aren't bad at all. The 6.4 likes the highway. If you were to ride exclusively on the highway your mileage would likely increase significantly. If I keep the speed to about 68 with my truck, I've gotten almost 19mpg on the highway (approx. 18.6 hand calculated). I've said it before that the 6.4 can sure feel like a hot rod, but if you drive it like a truck and not a car it can be a lot more economical.

I also agree completely about the oil changes. Diesel engines are not meant to be super clean burning engines, it's a low price to pay in my opinion for their greater fuel efficiency and power. Since all the new emissions junk has been foisted upon the modern diesel engines, the maintenance has become all the more critical. Keep the oil changed and fresh and you will likely get very good service from it. Keep an eye on the oil level and check the oil with the "short dipstick method" and don't let there be too much oil in the crankcase. Virtually all the problems that I've read about with the 6.4 could have been prevented with more deliberate maintenance. A few engines have made too much oil, or otherwise had oil related issues causing catastrophic failure. Also DO NOT use anything other than Motorcraft fuel filters and oil filters. You could conceivably use Racor as well, as they make the filters for Motorcraft but if you ever have a problem, you've got firmer ground to stand on with a Motorcraft proof of purchase. There is a difference in the Motorcraft filters and all the other manufacturers and those differences can lead to big problems.
 
   / My 2008 F450 XLT 4x4 6.4L #11  
The main reason to keep the oil fresh in the 6.4 is because it suffers from fuel/oil dilution more than the previous and current models, due to the regeneration process. It's not just a 6.4 thing though, it's an issue with both the 6.6 Duramax and the 6.7 Cummins of the same model years. Before DEF was introduced, the regeneration process basically consisted of the engine computer injecting large amounts of diesel fuel into the cylinders to get the EGT's up to super high temperatures, 1200F+, to clean out the system of any built up soot. Having that much fuel going into the cylinders though causes a good portion of it to end up in the oil, thus diluting it more than previous and current models. Keep the oil changed regularly and you shouldn't have a problem. Sounds like your happy with the truck so far. My future father-in-law just picked up an 08' 6.4 F-350 w/ 4.30 gears and it's a pretty nice truck as well.

:cool:
 
   / My 2008 F450 XLT 4x4 6.4L
  • Thread Starter
#12  
My truck is in the shop getting the gooseneck hitch put in it right now. I'll know how it tows in a few hours.

Brian
 
   / My 2008 F450 XLT 4x4 6.4L
  • Thread Starter
#13  
I really like this truck now. Makes me wonder why I didn't upgrade sooner. It tows my trailer nearly effortlessly compared to my GMC and my buddy's F350.

Brian
 
   / My 2008 F450 XLT 4x4 6.4L #14  
Do you have the built-in brake controller? Also, any fuel mileage numbers while towing so far?
 
   / My 2008 F450 XLT 4x4 6.4L #15  
I really like this truck now. Makes me wonder why I didn't upgrade sooner. It tows my trailer nearly effortlessly compared to my GMC and my buddy's F350.

Brian

I told you it would!
 
   / My 2008 F450 XLT 4x4 6.4L
  • Thread Starter
#16  
Do you have the built-in brake controller? Also, any fuel mileage numbers while towing so far?

Yes, it has the built-in controller and it works very well.

For the 646 miles I drove without the trailer the computer said I got 12.7 mpg, my math said 12.3 mpg.

So far with the trailer hooked up the computer says 7.5 mpg over 50 miles of driving. My GMC got a little over 6 mpg on average towing.

I was able to pull the mile long 7% grade coming towards my house at 50 mph and didn't feel like I was over working the truck. In my GMC that 8.1 would be screaming at 4500 rpm. The 450 did it at a little over 3000 rpm.

Brian
 
   / My 2008 F450 XLT 4x4 6.4L #17  
Yes, it has the built-in controller and it works very well.

For the 646 miles I drove without the trailer the computer said I got 12.7 mpg, my math said 12.3 mpg.

So far with the trailer hooked up the computer says 7.5 mpg over 50 miles of driving. My GMC got a little over 6 mpg on average towing.

I was able to pull the mile long 7% grade coming towards my house at 50 mph and didn't feel like I was over working the truck. In my GMC that 8.1 would be screaming at 4500 rpm. The 450 did it at a little over 3000 rpm.

Brian
7.5 mpg seems low. I have a 06 F-350 and my neighbor has a 07 Dmax 3500 and we can both get high 12mpg pulling similar loads.

I knew you would like that truck. The brake controller is sweet. You will never want to go back to using a aftermarket unit. I have had a Ford Diesel with the built in controller since November 2005 and its been flawless.

Chris
 
   / My 2008 F450 XLT 4x4 6.4L #18  
I was able to pull the mile long 7% grade coming towards my house at 50 mph and didn't feel like I was over working the truck. In my GMC that 8.1 would be screaming at 4500 rpm. The 450 did it at a little over 3000 rpm.

Brian
Technically, your comparing a gas engine with a rev limit of about 5500 rpms to a diesel engine with a rev limit of about 4500 rpm's. So neither were really "screaming" in terms of engine speed.
Either way, I was hoping to see a little better mpg's since your pulling pretty much half what the truck is rated for vs. a truck that was pretty maxed out.
 
   / My 2008 F450 XLT 4x4 6.4L
  • Thread Starter
#19  
I think that 50 miles is too small of a sample to fully determine what kind of mileage I will get overall towing. I'd really like to see 9 mph, but we will see.

Brian
 

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