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Why you dont like the ISX Engine.

Why kevin, dont you like ISX Motors? I listen to you kevin everyday. I love your show on Roaddog. I think you are really the best show on Sirius. I think I have heard you say that you prefer Detroit over the ISX? I love my ISX. It is the best pulling engine I have ever driven. I have driven for 27 years. I think it out pulls the old Cat Mechanically motors too. I thought they were the best in the business until I drove a 500hp ISX a few years back. I was amazed at the torque it has. I drove all over the western states, and use to haul Copper out of the mines in AZ. We pulled a lot of 7 to 10 percent grades and my first ISX motor was then. It was totally amaizing how it would out pull every othere truck or Motor on those hills. Our fleet was all 500hp ISX Motors,or Engines. Had one 600hp. The trucks all had 336 rears, with 13 speed trans. Loaded we always had 80,000 on.

Answer this question I have this problem too

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2006 T600 cummins isx 450 flywheel house leaking oil, front timing gear cover and front crankshaft seal leak oil,leak at oil cooler housing,oil leak at the oil pan gasket,radiator fins corroding away, transmission clutch release shaft bushings are worn out,transmission output shaft seal cover is leaking, coolant leak at the heater core hose connection,inter-axle driveshaft has play in the slip joint, play in the ball joint for the pitman to draglink end. The truck has 777,000 miles would buy this? or would get the shop to fix all of these things before buying???

by Jnn1011

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I have owned detroits, cats and cummins powered trucks. In my experience the series 60 Detroit gives the best MPGs. I have the fleet IFTA records for the previous two companies that I worked for. Both fleets had 2000+ trucks with a fairly equal mix of 14L Detroits in Columbias and Centurys and 15L ISXs in T2000, 387, and Volvos. All had EGR running standard OTR applications. Average MPG for the ISXs was 6.304 and was 6.823 for the Detroits. All trucks were goverened between 62-65 MPH. Again these are IFTA numbers which are much more accurate than qualcomm and reflect my real world numbers very closely. So running and ISX will cost around $5000 more oin fuel yearly no to mention the repairs which in my experience are more costly and frequent. This is painfull for met to admit since I drive an ISX now because I love Petes and didnt want an Acert so I had no other choice since you cant get a detroit in a Pete anymore. I have had numerous problems with this ISX and can promise you it will be the last I buy.

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Century? 387? Volvo? Right there is the difference... Freightliners are more aerodynamic than most of their competitors, but they are also lighter weight, rougher riding and typically have Detroits for the engines. The engine only makes up part of the equation of efficiency, the truck it's put in makes up another part, and the driver makes another part still. The Pete 387 (AKA the KW T2UGLY) and the Volvo are equal to each other aerodynamically, but they are not equal to Cascadia, Century, Columbia (which are roughly 3% sleeker). A half MPG difference between the Freightliner and the Volvo and PACCAR platforms, all other things (drivers included) being equal, is not unheard of. It's just simple aerodynamics combined with a great engine.

by Zachary

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by jaimeferreira

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Have to agree with other answers. ISX just not cost effective enough for me. I will be getting rid of it soon. Cummins had a great thing with the N-14. If the ISX has one thing great, it is the engine brake.

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I've had the Detroit series 60's and ISX's. Kevin is right on the cam issue, on my 2003, & 2004's they all needed cams around 865,000-920,000, the 2006 still has no issue and is well over 900,000 and I did have them checked. They have 2 cams and just that repair at Cummins is near $10,000. One I decided to overhaul instead at a cost of $22,000, another I bought a Recon motor which, with all the extras was about $26,000. Also just about any mechanic can work on the Detroit, I only will take my ISX to a Cummins shop. So they can be very expensive on maintenance, but I love them as well. The Cummins equipped truck is much more drive-able with the same drive train, 1850 ft lbs of torque vs 1550 ft lbs of torque in the Detroit. The Cummins equipped truck I drive averages over 8 mpg with all the upgrades that Kevin recommends. The Detroit only cost $16,000 to rebuild including the bull gear. Also it doesn't seem to matter what driver you put on that Detroit it gets over 7 mpg, I can put a driver in my truck and that 8mpg will drop to about 6.5 mpg!

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How are you tracking your fuel mileage? Dash display/EOBR/Qualcomm or Paper method/MyGauges? Just curious.

by Zachary

Always have checked fuel mileage by calculator at fill up. To me every fill up is like opening a Christmas present as a 5 year old boy on Christmas morning. So I've always known what I got before I even get inside to get the receipt. But now I also use Letstruck.com, fuel gauges, Disciple is the name of my truck.

by Steve

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It's simple business , nothing personal against cummins isx. 1# the most fuel efficient and cost effective truck engines on the road have been detroits.

2#. Cummins isx has had a reuccuring issue with there camshafts flattening out. First of coarse they said it wasn't there fault. Then they said yes they had a bad production run , but there all fixed now. Then they started up all over again , but the reason was because all you guys are putting those ops systems on your engines !!!!!!!!! Which we know is total nonsense. That is the reason Kevin has been a downer on the cummins.

If it makes you feel better ,, cummins is all we have and have great success with them.

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I was curious about the same thoughts, as I am looking for my first truck. All I seem to have been able to find are ISX powered units.

I asked a 18 year mechanic at my companies shop about this engine. I received the same response, they eat the cams, and he added that, while at his previous employer, they had over a dozen of the ISX engines break the crank at the damper. They just snapped right off.

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I have a 2011 ISX Cascadia. It is the best pulling truck I have ever driven, that is stock. I haven't had one bit of trouble with my ISX, I mean nothing. The camshaft problem everyone is talking about has been resolved by Cummins.

by Mitch Gaar

Mine just came out the shop for the cam issue. My truck made it to 808,000 miles. So I hope the problem is fixed. (I'll add a pic of one of the cams on the bottom) The repair cost $6,545. Cam, timing actuator, egr valve, 2x rockers(wich went bad due to the 2 cams) oil change and labor.

by James

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I like both the Cummins ISX and the Detroit S60 for the drive ability, however, they still don't beat an old CAT 3406E especially since a 3406 doesn't have EGR at all.

No EGR=No EGR issues.

It's nothing personal against Cummins, he just doesn't like what the EPA (Private Sector Destruction Agency) has shoved down the throats of ALL the engine makers. It seems he's had better luck with Detroit, but even those built after a certain model year have EGR issues of some kind.

BTW, he also doesn't like the Volvo D12 Vectro motor, either. That's why he calls it his favorite (for ALL of the EGR issues he's had with it). I don't know what his opinion would be on the Mack MP8 engine.

Kevin does not like anything with (MASSIVE) EGR (MaxxFarts, D12, ACERT, D13, XE13, among others) and that's for a really good reason. It seems Detroit did a really good job with the DD15, but that's probably the only engine I would go with if the truck was a 2007 or newer (AKA a beta test truck). If it's older than an '02, I would stick with my kitty, have an N14 BIG CAM Cummins or have a Detroit S60 (those were good engines). If it's in between, the ISX, despite it's cam issue, the ACERT CAT and the Detroit S60 would be a toss-up.

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Take a serious look at the 505hp 12spd o.d., 3;58 rears, MP8 Mack.Our fleet is avg just short of 8mpg.

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How much time has that engine spent in the shop for repairs in the last year? I would like some feedback, since the Volvo D12 is Kevin's (Least) favorite motor and is a cousin of the MP8. Has it been more reliable than it's distant Swedish cousins (D12, D13, XE13) or has it been about the same?

by Zachary

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the software,and hardware is different.They are programed different.

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That doesn't answer my question about how reliable it has been for you specifically, but the programming, hardware and software certainly can make or break an engine during it's first couple of years. I am considering Mack and it's sister company Volvo as options for a truck some time down the line if I don't end up buying what I have now, because I really like the looks, ride, power and efficiency. My question is how reliable this truck has been for your specific application.

by Zachary

My MP engine is great 800,000 and never cracked opened uses a gallon of oil every 18,000 miles

by Your

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This a cam on my bad cam shaft. Notice how in stead of going flat across it has a wide groove. I now have a new one so I hope the problem is fixed.

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What brand of motor oil did you run when this happened I am curious

by Mel

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All of the fleets I've talked to have about 100000 miles and no issues.Talked to drivers at Sharkey,they are not having any problems with the 2013's,and most are getting 8mpg.

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I have had many problems with the 2001 ISX as I had turned it up from 450hp @1650 tq to 600+hp@ 2050+ tq . number 5 piston turned sideways a few months later . now it is a real 600hp @ 2050 tq . and no problems yet . I have used the new monotherm pistons . power is soother than a v16 and gobs of power throughout the r.p.m. range . I out pull old yellow set 2@ 600 . on all hills set weight the same . SMOOTH POWER is what sells me . not to mention 40++ more % engine brake . I highly recommend the concept timing gears !!! It is 0.00 % backlash and think it could help the cams ?? I pinched off the waste gate line and am careful not to boost over 34 lbs on hills and the fuel mileage is now like it was as a 450 or more, but soooo much more Torque . I am pretty sure I am the only one with a signature 600 in a ` 01 FLD120 the only one !! can`t wait to get a oil Spinner II 960 put on .

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I DO miss the N-14! ..but hey . You can`t have good things when the government gets done with anything !! N-14 never cooked fuel,ran cooler . and it would spank a Detroit in ALL ASPECTS !! , PERIOD !!...maybe even a few kittys too??

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very late comment here, so sorry for that, but an N14 will beat a Detroit in every aspect EXCEPT fuel mileage. If all things were equal except the engine, the Detroit will wipe the floor with an N14 on fuel.

by Justin Van Derslice

Kevin and Bruce from Pittsburgh Power are now talking about building gliders with the N14 Cummins and Bruce believes he can beat the series 60 in fuel mileage with the N14. Kevin is not sure about it yet. We will just have to wait and see what the results are.

by Rick

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My family had 3 Cummins ISX's in the first part of the last decade, 2 '99's and and '01. All three had major catastrophic failures before 800,000 miles. The two '99's had both been rebuilt under warranty for oil consumption, so their failures in the 6-700,000 mile range were really tough to take. We weren't using bypass oil systems back then, just changing the oil every 15K like everyone else. One '99 seized up dropping off Flagstaff, my brother was fortunate to have enough air to get stopped. The other two just threw rods through the block...

When they were running they ran great. My '99 was a 600, 2050 torque. There were VERY few trucks(including the 600 cats) that could beat me up a mountain, and the mpg was decent for the way I drove it. We also had our share of turbo and camshaft issues.

My current truck is an '06 accert with over 950,000 miles and never even been on a hook.

You couldn't give me another cummins powered truck.

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I have a 2012 Pete and a 2013 Kenworth both with 15 L Cummins. They are both at Peterbult with Engine problems. These engines are junk!! Service and sales guys at Peterbilt have told me to stay away from the Cummins engine. Paccar engines are he way to go.

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Rawze.com, come join us, there is a fix...

by Waterloo

Problem with Paccar, I've heard (including from dealers) is that there are fewer places you can go for repairs. Not a problem if you stick to locations that are close to such shops, but a problem if you're OTR covering all lower 48.

by Dhansen01

I'm with Waterloo. If you're going to rely on the stealerships to fix your truck, you will go broke with any newer engine. At least with an ISX, you can do almost anything you need to do with the engine yourself, saving the cost of paying people who don't know/don't care what they're doing to fix your engine. You just have to have some mechanical abilities and you can't have the fear of getting your hands dirty. Rawze.com has answers.

by Tim

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Have a 2009 motorhome with an ISX 650, 2nd owner. Turbo went out at 11,000, repaired under warranty.

Broke a valve off in #6 at 19,000 miles again under warranty, now at 44,000 miles it again broke valves in #5 and 6, liner in 4 also needs replacing. Cummins admits that they have a problem with the engine breaking valves and have new heads and valves to "fix" it. Bill is right at $29,000 and so far no word on Cummins covering any of it. Cummins NW says they have seen 4 of the ISX's do this, 2 MH's and 2 class 8's so it's not uncommon.

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Well Cummins called today and the DPF is cracked so the bill is now $31,000, but they are covering about $10,000 of it. So much for Cummins building great engines!

by DeenAd

I warn these people buying these emission engines in Motor Homes, yet they just claim; "I have X,000 number of miles on my emission engine and no problems." Then they go and recommend to someone to buy that emission motor. But this is the same story I hear from all the emission motors, not just cummins. If I'm buying a Diesel, whether it's a truck or a MH, it's going to be a pre-emission motor! And I'm talking 2003 or before.

by Steve

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Hey guys I'm buying 2007 Volvo with ISX 450 cummins engine do u guys dvice me to buy it

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I would not. But then I wouldn't buy any emissions engine at this time. I've had 5 ISX egr trucks from 2004 to 2006, and only one of them is still running. My 2003, which is my personal truck, at 1,200,000 miles I ordered an Cummins Recon from the factory. Once it got in I drove the truck to the dealer to have it installed. Disciple is my truck on fuel gauges, so you can look to see my fuel MPG and all the upgrades. The power is much better than my detroits. But my first motor was a Formula 290 that I purchased in 1981. With the Cummins, how it is driven is very important. I put a driver in this truck and he couldn't get over 6mpg, I average over 9 mpg. My detroits were always in the 7mpg range no matter who was driving.

by Steve

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I have 2011 Pete with ISX cummins with dpf Def scr all the emissions and it's been way less pain in the @%^ than my detroit ever was so there's no way I'll ever own Detroit again

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That's what I had for three years, and it was a three year nightmare. In the shop about once a month the entire time. The DPF system was a disaster at the start, but then eventually Cummins made some upgrades (programming changes, larger filter) and then the problems were fewer, but still happened.

by Dhansen01

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Guys i need suggestions we haul Fuel in new jersey north east mostly i have 3 choices isx 13L (pete379) Paccar or mp8 (mack )what are the suggestions based on all your experience ( if cummins made any progress for 2015 )

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Mitch Gaar will be eternally grateful.

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