5.9, 6.9, or 6.7 Cummins pros and cons

Hey guys looking to get me a 5th wheel here very soon so have to get a diesel. My question is as in the title what's the best out of all 3 and the pros and cons on all the motors. Any specific items that are known to fail.

Thanks for all the advice in advance.

What is a 6.9? Are you referring to the 6.9 IDI that ford used to use?

6.4?

If you want new diesel it's the 6.7 cummins. Used up to 06 or 06.5 is the 5.9 and if you find one with low miles they will charge a premium for it. Highly desirable without the emissions crap of new.
I wanted a cummins to tow my travel trailer but only tow it 8-10 times a year so I went with a half ton. Couldn't justify the extra costs up front, for fuel and for maintenance. If I towed heavy all the time I would get one.

I had thought dodge had made a 6.9.

Well I'll only pull mine a handful of times a year but being I'm buying a 5th wheel I need the diesel.

Anyone know of any pros or cons of the 5.9 or of there was a rough year? If its stock going to change it but would like to know of there's things I need to look out for.

There are 2 different 5.9Ls..a 12 valve and 24 valve. Bulletproof motors. Had a longhauler at work come in towing a gooseneck with a 2004 24v 5.9 3500 drw with 450k miles on the original motor and tranny. That was with a 45re tranny too not even the manual. You cant go wrong with these motors if theyre properly maintained. Your problems are gonna be with the rest of the truck more than likely.

I remember my dad having a 97 5.9 I wanna say 24valve ran for 600k before we finally sold it.

I would really like to get a 5.9 cause without emissions crap and can do whatever.

Are they're any recommended upgrades?

Jerry1984 said:

rge a premium for it. Highly desirable without the emissions crap of new.

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07.5
My trucks an 07 5.9

You should really consider a 6.4 Hemi depending on the weight your towing and how often
Just cause it's a 5th wheel doesn't mean you NEED a diesel

There are million mile 6.7s out there too

I did consider the 6.4 hemi, but I just feel like a diesel is better especially for the long run. Cause there's time I may have to use it to pull things for work.

I don't doubt it, I've always believed that your routine maintenance is the biggest portion of a trucks life.

How big of a 5th are you getting? Longevity of the 6.4 really shouldnt concern you too much unless your looking at 13k with many hills, towing frequently or driving way more per year than the average person, the 6.4s lifespan should be more than satisfactory for you. Not that its been documented but the motor was designed with longevity in mind at least.

The 2 were looking at right now 1 is 32 other is 38. Right now the heaviest were looking at is 12k I believe.

I do turnarounds for a living so we travel across the U.S. for work. So it's going to be a work horse not going to be babied by any means. I would say I would be pulling the trailer at most 1 time a month.

Sounds pretty cool to me..definitely diesel then imo

If it was me I would go for a 04.5 to 07 5.9 Cummins those particular models they had more horsepower, and more ft lbs of torque. 04.5 to 07 had the HE351 bigger turbo and better waste-gate compared to an 03, 04 models which had an HE341 smaller turbo , but they had no kitty cat(converter). Unless your were in the state of California. I had an 03 original owner, great truck never any issues, had over 350,000 miles on it . It got stolen back in 08, insurance declared it a toatal loss, that's when I obtained my 6.7 Cummins. The 6.7 Cummins is as strong if not stronger than the previous 5.9. They used 40 percent of the parts from the 5.9 to the 6.7, they had to bump up the displacement to make up for the strict emissions loss for the 6.7. The 6.7 has bigger bore, bigger stroke, when emissions are deleted is as good if not better than the previous 5.9. The emissions kill the 6.7, when the warranty is up it can cost thousands of dollars to fix, all being emissions related issues only! If your looking to obtain a diesel, your best best is 04.5 to 07 5.9.

I just felt it was better but I do greatly appreciate the question to better help answer.

Okay thanks Cummins Powered. Do you have any recommend upgrades you would do?

Well if you decide to go with a 3rd gen 5.9 which is 03 to 07 models, 04.5 to 07 had the HE351, bigger turbo with a better waste-gate turbo actuator with a little more horsepower and torque. If you decide to go with an automatic which is the standard 48RE 4 speed, descent transmission, some were reporting 400,00 miles used for Hot Shot, stock mode. I had the 03 with over 350,000 miles with the 48RE with a BD Diesel torque converter with some highly other modifications. My wife has an 06 5.9 with the 48RE with the Banks Power triple disk torque converter, H&S Mini Max, Banks Monster High Ram intake manifold with Banks grid heater delete, AFE mega canon cold air intake, BD Diesel exhaust manifold,injectors, Air Dog II 165, BD Diesel intercooler, Bully dog 6 inch turbo-back, which is 5 inch down-pipe from the turbo after the down-pipe flared to a 6 inches in diameter to the end of tail pipe, straight pipe, stock turbo silencer ring removed with a Wicked wheel compressor. Other option is 07.5 to 09 6.7 Cummins still with the 3rd gen body style, turbo is HE351 compressor housing bigger with VGT turbo and built in factory exhaust brake. The VGT turbo greater spoiling times with less lag, great trucks came with 6 speed 6R8E more like firmer shifting car like shifts, downfall the emissions. When emissions removed totally different truck, sounds different because of the VGT turbo.Then of course the 4th gen 6.7, body style came out in 2010, great appearance inside and out. Great truck, again the downfall hot robbing engine emissions. Now you will have to decide on which Cummins you will favor and go with, the 5.9 Common rail, 03 to 07, 6.7 3rd gen 07.5 to 09, or 6.7 4th gen 2010 to current body style. Either with emissions, or without.

Great info thanks!! Cummins powered.

So far all the ones I've looked at have been all the 5.9 and 1 6.7 I'm really hoping to get the 5.9 hopefully to have it this coming up week, and then since I'm going to drive it till it stops start modding it.

Do you have websites to a place that sells parts at decent price?

6.4 comment from regular cab

Well, you described me exactly. lol Will better tell you how the 6.4 holds up after this summer. I do tow a 13k 5'er and will be towing much of the time with it this coming summer. My thought, after getting the gearing for towing, that 100k will come and go and have no problem with the engine or trans. As for today, have seen no problems with ether and the mileage, considering the 4.56 gearing, I feel is still good. When towing, hope to average near 12 mpg overall in our travels as getting about 10 in higher elevations in Colorado now. Truck just turned 15k miles last week so not really even fully broken in yet I suspect. Wish me luck. lol Ps. Just to say, the 2500 handles the trailer very well suspension wise and the trailer tow and engine braking work well also. Just got pin weight last week on the 5'er and was just over 3200#.

The 2006 and 2007 5.9 cummins is what i would recommend. I recently traded an 06 for my 2015 6.4 hemi...

I went with the 2006 because of the updated trans, updated computers and some small stuff under the hood like earlier years used plastic inlets to the intercooler that tend to break... The 2006 and 2007 also allow for EFI live tuning to be done.

If you go with a 5.9 make sure you get the manual trans. I opted for the auto at the request of my wife so she could drive and i ended up hating the 4 speed trans. It worked, and it worked well but i felt that i couldn't get it dialed into what i really wanted to...

quick story, i ran from Lincoln NE to Estes Co with a 10,000 bumper pull trailer and the truck only down shifted once out of 4th running 67mph the whole trip there... other than getting on and off and going through towns obviously... the truck handled great... just wanted the creature comforts of the newer models...

CumminsTxBoy89 said:

Great info thanks!! Cummins powered.

So far all the ones I've looked at have been all the 5.9 and 1 6.7 I'm really hoping to get the 5.9 hopefully to have it this coming up week, and then since I'm going to drive it till it stops start modding it.

Do you have websites to a place that sells parts at decent price?

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Your best bet would be Xtreme Diesel Performance, they carry all your diesel needs from BD Diesel Performance, Banks Power, PPE, H&S Performance, Sun Coast, DPP, Industrial Injection, Bullydog, Edge, ATS, Smarty, you name it they carry all the big names for the aftermarket diesel performance parts. I've obtained many parts from them over the years from my past to present diesel trucks. There located in New Jersey, prices are cheap, and they will compete prices with the competition. I also see that they have there advertising on this site.

Thanks for all the awesome advice and tips guys I really appreciate.

Just found out it's got to be put on hold for now, which that's fine gives me time to really search, and not settle and find what I want.