400hp 9.2ISL Cummins or 400hp C9 Cat

[tropical36]

Pros and Cons please and do realize that some of this stuff is like arguing Ford vs Chevy. Thing is, I'm not even in the ball park when it comes to Diesel power.

[TDInewguy]

I have the 3126 in my 2002 Itasca Horizon - and it's the early version of the Cat C7. The C7 change was partly due to the emissions stuff and I'm glad I don't have that - as the MPG suffers.

My 3126 now has 92K miles on it, and if I'm not towing anything and keep the speed to around 62mph I do get 9.5-10.5 MPG (also with no headwind)

Towing I usually get around 8-8.5MPG if I have my 33' long enclosed trailer.

I really wanted to get the ISB engine, as they were known for good MPG, but the coach I found had the floorplan and price that was nice, so I got the engine I got, and it has performed well for me as I bought it with 24K miles.

[wolfe10]

I think some confusion has entered this thread.

OP is comparing the Cat C9 and Cummins ISL.

Same size/displacement and HP.

The C7 is a smaller engine (7.2 liter vs 8.9/9 liter), but a very widely used one.

[DSDP_Don]

No matter how you look at these two engines, they were/are both popular in certain brands over certain time periods. The Cat C7 was the engine to have when it started showing up in DP's. Then the manufacturers started gravitating toward the Cummins ISL when it came available. The Cat C9 started showing up in certain brands like Beaver and a few others. At some point Cummins started to dominate the market.

Soooooo.....either will be a good engine, it just depends on your budget, which will dictate the year of coach you can afford, which will dictate which engine was the most popular then.

****Wolfe....I had C7 on my mind when I posted, but still the same outcome with engine availability. I corrected my statement.

[nemo45]

bluwtr49 wrote:
Since a Cummins or a Cat are the most prevalent engines for MH's it's not something to fret about. Both are great engines. Noise??, I'm not sure you can tell the difference while driving. I hear a lot of both and they all sound the same to me unless the muffler has been changed than either is load outside.

I have a friend with a Cat 350 that I have been traveling with for four years. We have a ISL400 Cummins. I'm sure you can't tell the difference driving down the road. But, when we pull into a rest stop and leave our engines running you certainly can tell the difference. His is much louder than mine. That being said. He gets nearly a mile per gallon better than I do. Not sure if there'd be that difference if he had a 400. My coach is much quicker when pulling out on to the super slab. Probably the difference in torque.

[Bruce_Brown]

DSDP Don wrote:
It's hard to quantify, but I agree with "sprintmod1" on the two engines. My sister had a 34' DP with the 350 Cat. I had a 36' DP with the 400 ISL. Their coach was quicker, but I soon pulled away from them. When we would fuel up, I always look a less, (about 1/2+ mpg better) even though I had a larger coach and engine.

I know many of the older 525HP Cats, drank a lot of fuel. I don't think you can go wrong with either engine, but my vote would lean toward the Cummins.

That 350 Cat was based on the old 3126 - but at 7.2L it's not a small block but certainly not a big block either. It was also only rated at 860 # TQ.

The 400 ISL is rated at 400/1200, and is 8.9L large.

I'm guessing - only guessing, theirs was geared a bit lower.

Our last MH had the 7.2 Cat, or current MH has the ISL. The difference is night & day. There is no replacement for displacement. :B

[moisheh]

I don't know why everyone calls the 05 engines pre emissions. They are pre DPF but still have emission programed ECM's . The Acert Cat's have EGR. The big Cats of that era have big problems with the twin turbos and the EGR set up. In the trucking world pre emission refers to pre 02 or 03.

Moisheh

[J_R2]

We ordered and took delivery oct 2005 of our o6 Rev LE40E. Bath and a half. C9 cat, pre-emissions. 90,000 miles no regrets. 8mpg. Just follow a maintenance schedule.

[DSDP_Don]

It's hard to quantify, but I agree with "sprintmod1" on the two engines. My sister had a 34' DP with the 350 Cat. I had a 36' DP with the 400 ISL. Their coach was quicker, but I soon pulled away from them. When we would fuel up, I always look a less, (about 1/2+ mpg better) even though I had a larger coach and engine.

I know many of the older 525HP Cats, drank a lot of fuel. I don't think you can go wrong with either engine, but my vote would lean toward the Cummins.

[tropical36]

Blackdiamond wrote:

tropical36 wrote:
I appreciate the feedback so far, and we've been sort of, sort of, looking at the earlier Fleetwood Revolutions which were built on the American Platform and the Spartan chassis, but weren't called American and not until about 2012 or so.
Looks like the 06 and 07 are Cat engines and the 08 being a Cummings.
Really like the 1 1/2 bath model and the quality look of these coaches in general.
So what about parts and labor costs between the two, if and when that's needed and something the average gear-head doesn't want to do for themselves?

My vote would be the 07 and earlier, not because of the cat, just due to the fewer smog controls on the pre-08' engines, the new laws made cat leave the market.

Good to know and always wondered why the Cat pretty much disappeared from the RV market.

[Bruce_Brown]

Blackdiamond wrote:
My vote would be the 07 and earlier, not because of the cat, just due to the fewer smog controls on the pre-08' engines, the new laws made cat leave the market.

Thats one of the reasons we bought when we did. Our MH is an '08 with a '06 spec engine in it. No smog, no DEF, no ultra-low sulfur required. The best part was seeing as they needed to go, the normal $6800 adder for the ISL was waived. Win! :B

[Blackdiamond]

tropical36 wrote:
I appreciate the feedback so far, and we've been sort of, sort of, looking at the earlier Fleetwood Revolutions which were built on the American Platform and the Spartan chassis, but weren't called American and not until about 2012 or so.
Looks like the 06 and 07 are Cat engines and the 08 being a Cummings.
Really like the 1 1/2 bath model and the quality look of these coaches in general.
So what about parts and labor costs between the two, if and when that's needed and something the average gear-head doesn't want to do for themselves?

My vote would be the 07 and earlier, not because of the cat, just due to the fewer smog controls on the pre-08' engines, the new laws made cat leave the market.

[jplante4]

When I said my CAT was louder, I meant standing next to it outside while it's idling. Granted, most coaches are newer than mine, but I made the same observation on the Ford pickups my neighbor had. He is a contractor and bought a new Ford pickup every year. When he went from the CAT powered one to whatever Ford used next (Duramax???), it got a lot quieter idling to warm up in his driveway 7:00 am every day. The CAT always sounded like it was about to throw parts out the side of the block. The 3126 in my Sahara has a similar sound.

[tropical36]

sprintmod1 wrote:

tropical36 wrote:
I appreciate the feedback so far, and we've been sort of, sort of, looking at the earlier Fleetwood Revolutions which were built on the American Platform and the Spartan chassis, but weren't called American and not until about 2012 or so.
Looks like the 06 and 07 are Cat engines and the 08 being a Cummings.
Really like the 1 1/2 bath model and the quality look of these coaches in general.
So what about parts and labor costs between the two, if and when that's needed and something the average gear-head doesn't want to do for themselves?

I have owned both. The Rev's have been built on the AC line and the early run of 2010's is when they changed the decals from Fleetwood to AC. Currently have a 2010 AC Rev with the 8.9 Cummins. There is a difference. The Cat has all types of power especially from a dead stop to 55mph. The down side to that power is it is about 1mpg lower than the Cummins. With the Cummins, the get up and go from a dead stop is much slower, powerful, just much slower. The up side to that is we are averaging about 1mpg better than the Cat. Once over 50mph, I don't feel any difference in the engines and we are generally pulling a 14000lb trailer. The Cat's do like to eat!

Since 2007 the on road engines have some sort of smog system on them. My Rev is currently at 120000+ miles and we are having various issues with the DPF system and that is costing some major dollar repairs. And by a few months after the government mandated five year warranty has expired on the emissions system to boot.

Given a choice, I would take a Spartan chassis Rev over a Freighliner and the Cummins over the Cat due to the large amount of miles we rack up every year. The fuel savings have so far exceeded the maintenance costs. Your results may vary.

Good luck with the coach search, it can be frustrating, but when you find a good one, it will be worth it!!!

Good that you brought up this smog thing, which I keep hearing about and not much good to be said of such.
So, you're saying if you want to stay away from these systems, stick with the 2006 model.
As for the engine size, this 9.2 liter thing came from a sales advertizment and have no idea if that's correct or if it is in fact an 8.9 liter. Either way, there's a lot of talk about ISL engine failure on the net, so again, I'm clueless.
Now, if one was to stick with the 06 model Revolution, then they would have a Cat C9 anyway, along with whatever problems they've been noted for.

[bluwtr49]

sprintmod1 wrote:

tropical36 wrote:
I appreciate the feedback so far, and we've been sort of, sort of, looking at the earlier Fleetwood Revolutions which were built on the American Platform and the Spartan chassis, but weren't called American and not until about 2012 or so.
Looks like the 06 and 07 are Cat engines and the 08 being a Cummings.
Really like the 1 1/2 bath model and the quality look of these coaches in general.
So what about parts and labor costs between the two, if and when that's needed and something the average gear-head doesn't want to do for themselves?

I have owned both. The Rev's have been built on the AC line and the early run of 2010's is when they changed the decals from Fleetwood to AC. Currently have a 2010 AC Rev with the 8.9 Cummins. There is a difference. The Cat has all types of power especially from a dead stop to 55mph. The down side to that power is it is about 1mpg lower than the Cummins. With the Cummins, the get up and go from a dead stop is much slower, powerful, just much slower. The up side to that is we are averaging about 1mpg better than the Cat. Once over 50mph, I don't feel any difference in the engines and we are generally pulling a 14000lb trailer. The Cat's do like to eat!

Since 2007 the on road engines have some sort of smog system on them. My Rev is currently at 120000+ miles and we are having various issues with the DPF system and that is costing some major dollar repairs. And by a few months after the government mandated five year warranty has expired on the emissions system to boot.

Given a choice, I would take a Spartan chassis Rev over a Freighliner and the Cummins over the Cat due to the large amount of miles we rack up every year. The fuel savings have so far exceeded the maintenance costs. Your results may vary.

Good luck with the coach search, it can be frustrating, but when you find a good one, it will be worth it!!!

Good comparisons between the two engines. Though it almost sounds like the difference could be accounted for by different gearing between the two coaches.