MPG's on 4.5 HO 600 AWESOME!!!!!!!!!!

[roperteacher]

Well, I had to break in the new rear gears today so went on a drive up to see the folks. Flat level ground, no wind, cruise set on 63MPH the entire way!!!! Perfect fill up to start the trip and stopped to fuel up after 227. 0 miles. Took 8. 9 gallons!!!! OVER 25 MPG!!!!! It has steadily been increasing since the first tank! My truck is an 4. 5 600 HO 4X2 long bed, 3. 73 rear gears 6 speed. Only 150 more miles to go before I can pull that trailer tomorrow as per dealer recommendations on new rear gears ( 500 miles, no towing, never over 65 sustained speeds... )

 

[boonsur]

Nice! Although it'll drop quite a bit when you go above 70-75.



How's the new rear-end. Any noise, at all?

 

[roperteacher]

Nope, no noise!!! Smooth as a bell. I went ahead and took the dealers advice and didn't tow until 500 miles. And I have to set the cruise or I get to rolling way to fast. I took her right up to 70 as I was leaving the dealer parking lot so I could make sure no noise. I did as others suggested and drove 20 mi, stopped a few minutes, etc. . anything to help! So far I am satisfied. I've never had a NEW truck with a problem before, but I guess it happens. A lot of folks on here had the same problem so I don't feel so bad...

 

[roperteacher]

On the trip home I got 24. 1 MPG!!!!!!!!!!!!!!! SOme head winds for about 40 miles of the 280 mile trek! I'm very pleased!

 

[mfrost]

That's super mileage! I'll never see that since I have all of the fuel guzzling goodies on mine Your profile doesn't say if your rig is a 2500 or 3500. What is your build date?



Have 8000 miles on mine and runs great. Oo.

 

[KevinO]

I can't get better than 13 no matter how i drive have 3000 on the odometer now. put a ez from a buddy on and mileage went up a couple mpg's liked the extra hp and no hesitation off the line. I had the reflash done but there is no underhood sticker to say it was done. I drive alot of miles for work and need more mpg.

 

[roperteacher]

I keep forgetting to sign my signature to my posts!! Build date of Feb 8. 2004. 5 600 4x2 2500 LWB. Stock everything 6 speed

 

[JWerkheiser]

I was so excited the other day I got almost 25mpg on the over head. I reset it at the top of the hill, when I got to the bottom it was 24. 9.



Still getting 12-14 at best.

 

[carson6]

so there is hope....

because 11. 8 $uck's!

 

[RobbieH]

Originally posted by roperteacher

I keep forgetting to sign my signature to my posts!! Build date of Feb 8. 2004. 5 600 4x2 2500 LWB. Stock everything 6 speed

You have the same truck as me if you have a quadcab, but mine is an '03. We seem to have the best truck for high MPG.

 

[DIESELMAN]

Originally posted by JWerkheiser

I reset it at the top of the hill, when I got to the bottom it was 24. 9.

Hmmmm, I got 99MPG when I reset at the top of a hill, I'll just drive downhill everywhere!

 

[DIESELMAN]

Originally posted by JWerkheiser

I reset it at the top of the hill, when I got to the bottom it was 24. 9.

Hmmmm, I got 99MPG when I reset at the top of a hill, I'll just drive downhill everywhere!

 

[NDanecker]

First tank hand calc at ~17. 1.



Oo. I'm happy!

 

[Jeremiah]

Best mpgs

Originally posted by RobbieH

You have the same truck as me if you have a quadcab, but mine is an '03. We seem to have the best truck for high MPG.

I agree. I too got 24-point-something or other driving a steady 62-63 mph from Colorado to Omaha. That's 1800 rpm. I drove posted speeds (75 on Interstates) coming back and still did better than 19. I live at 9,000' and get 20 to 20. 3 or so up and down the pass where I live. That's calculated now. The only overhead I look at is DTE and I can drive 700 miles before hittin' zero. But after that it's :--)

 

[RobG]

And yet my dealer tells me he can't do anything about the roughly 11-11. 5 mpg that I get EMPTY in my '03. 11,500 miles and that's all she'll get. On the freeway I MIGHT see 13. That's posted speed limits 65-75.



Towing I get 9-10. That's 5000 lbs of enclosed trailer.



It's time to ditch this POS... second Dodge in a row with crap mileage.



Rob

 

[Bertram65]

RobG, nothing against your truck but you have the worst possible combination for mileage, 4X4, automatic, DRW and 4. 10s.

I get about about 16 unloaded on the highway, and I almost never go over 75, I think the 4X4 and the auto are the biggest mileage killers.

 

[KBertetto]

Roperteacher... . what was your MPG's prior to the rear end being replaced? This could lead to some sort of an explanation as to why some trucks get terrible mileage and some do pretty good. This is just a thought and maybe I'm really reaching here but for the guys getting bad mileage we should try and get every possible idea on the table. My 600 is still doing good on the highway, nearing 22 @ 65mph. Congrats on your fix, happy to hear your rig is fixed up right!!

 

[Briman]

Originally posted by RobG

And yet my dealer tells me he can't do anything about the roughly 11-11. 5 mpg that I get EMPTY in my '03. 11,500 miles and that's all she'll get. On the freeway I MIGHT see 13. That's posted speed limits 65-75.



Towing I get 9-10. That's 5000 lbs of enclosed trailer.



It's time to ditch this POS... second Dodge in a row with crap mileage.



Rob

Maybe you'll have to start taking your Rincon instead of your truck.



The Dodge dealership doesn't have the same owner as the Honda dealership does it?



I thought you liked your truck. I get over 19 mpg with my SRW 3500.

 

[WStoops]

I just got back from my first highway trip in my 04. 5 600, 3500, Laramie, SRW. 3. 73, Auto. 4x4, short bed. 19. 48 hand calculated while the overhead said 17. 5. Did go through a few measured miles and the speedo appears to be exactly on. My around town has gone from 15. 1 to 17. Have 1200 miles on it, all driving easy. Not sure I agree that pushing it hard right out of the showroom is the way to go. That seems contrary to all of my mechanical experience. 25 years as a tech and service mgr, bus owner, ASE Master. Highway speeds of 65. Bad vibration at 70 (2,000 RPM) which I will begin to address tomorrow. My sense is that it is a rotational imbalance, probably in the driveshaft. Seems to get a little better at 85 mph. Extremely faint vibes beginning at 65. Continued operation in the range of vibration is really ill advised. A vibe of that intensity WILL damage something, universals, seals, etc. sooner than later. Could also be a tight universal joint. It seems to have gotten very slightly better after my jaunt to 85+ mph.

 

[roperteacher]

Wow. this post popped back up after a while! Truck goes back in the shop tomorrow to have the rear end looked at again!! No whine at 60-65 anymore... . but 65-70. Most noticeable at 67-70. Might need a whole new axle assembly...