Community Forums

Hork · 11-12-2020, 10:45 AM

Pretty impressed with engine so far. Drove 70-75 and got slightly over 10 MPG. Second tank pulled it back to 1500 RPM, about 66-68 MPH and got 11 MPG. Have an ABS light on which was there at purchase (dealer is reimbursing the repair) but that is a chassis issue and not engine related.

Overall, VERY quiet, air conditioning cranks, plenty of power. Way better than the gas Class A we had when I was a kid. That thing was loud, doghouse got hot, terrible mileage, underpowered, and couldn't get out of it's own way!

Hork

vnorvi · 11-13-2020, 01:41 PM

Quote:

Originally Posted by VestaDave

The MF 7 was installed in Breeze, Nexus, Vesta, and Serrano. There may be others but the point is, all told they are in a relatively small number of Motorhomes. But remember, they were also installed in school buses and trucks. I don't know how many but my guess is that the number in service gets much bigger. Looking at this site and elsewhere there seems to be relatively few complaints about the engine. It's true, that Navistar screwed the pooch on their approach to the 2010 emissions. I believe the MF 10 and 7 were the only two motors of their line that met the standards. As a result the company is not only facing lawsuits, they lost billions in revenue!
Bottom line, the motor has performed flawlessly and no DEF needed while returning amazing Mpg ( in my opinion).

We had our Serrano for 30k with no issues, towing a 5k pound jeep. You can be certain the rubber tube connecting the air intake to the turbo will fall off at some point. The use a 5$ clamp instead of a 10$ Clamp, snd this is the source of all the internet buzz. Thor has an upgraded clamp available. Bigger clamp, and comes with glue (seriously). It won’t fall off, and then all is good. Be SURE that anyone doing an oil change knows to clamp this down well. Most will undo the clamp to get to the oil filter, and you need to be sure they really clamp it down when they are done.

Jdsandb · 11-14-2020, 06:25 AM

Quote:

Originally Posted by vnorvi

We had our Serrano for 30k with no issues, towing a 5k pound jeep. You can be certain the rubber tube connecting the air intake to the turbo will fall off at some point. The use a 5$ clamp instead of a 10$ Clamp, snd this is the source of all the internet buzz. Thor has an upgraded clamp available. Bigger clamp, and comes with glue (seriously). It won’t fall off, and then all is good. Be SURE that anyone doing an oil change knows to clamp this down well. Most will undo the clamp to get to the oil filter, and you need to be sure they really clamp it down when they are done.

Recently turned 42,000 miles on our 2013 Serrano. Drove it from our home in MN to an RV park in AZ (where we plan to stay off & on during the upcoming winter) Total trip @ just under 1,800 miles, with average speed around 70 mph. Managed just over 10 mpg on the trip. The Maxxforce 7 performed flawlessly through various terrains! After replacing the often-referenced diesel turbo tube & clamp, so far we couldn't be happier with the overall performance of this motor!

Hork · 11-23-2020, 04:45 PM

Well, we pulled the trigger and bought a Serrano 34M (bath and a half). Bottom line is that we love the floorplan and styling (ie. different). Drove 560 miles home from purchase, ran great. First tank ran 70-75 mph and got 10 mpg, some hills in VA/WV/PA. Second tank pulled back to 1500 rpm which was about 65-68 mph and got 11 mpg!

First impressions: Great mileage, seemed to have plenty of power, amazingly quiet once up to speed, doghouse was not hot, and factory A/C cranked!

Had two gas RVs as a kid, one Class C and one Class A and I remember them being loud, hot, and not being able to get out of their own way.

Will be counting on you guys to help me keep this rig up and running; wife and I are planning to put some money into the old gal in mods and restoration's. So far I have learned from all of you that oil changes RELIGIOUSLY at 5,000 miles are non negotiable, 1500 rpm is a sweet spot in this and most diesels, long periods of idling are very bad for this non DEF setup, and inspect the turbo clamp and replace with one available from Buddy Gamel.

You guys rock for so freely sharing info.

Hork

vnorvi · 11-24-2020, 10:29 AM

One other minor lesson we learned. When the oil is changed most mechanics will remove the turbo tube to get to the oil filter. Of these, only about half of mechanics will tighten it down well after they are done. Be sure to make sure your oil change person knows about this in advance.

MANALPINE · 12-03-2020, 02:51 PM

Quote:

Originally Posted by Hork

Thanks for the reply. Pulled the trigger on a Serrano today; pretty excited about it.

I know you just bought your serrano . what do you think so far with the Maxxforce 7? Any issues? we are looking to purchase a serrano also here next week.

thanks
manny

Freddyjoe · 12-04-2020, 06:23 AM

Bought it at 28K miles, and now at 52K...

Never had problems, run smooth and very efficient. My mecanics told me to change oil every 5k miles or more often and that is what I go with.

We really like it.

Hork · 12-04-2020, 10:33 AM

Quote:

Originally Posted by MANALPINE

I know you just bought your serrano . what do you think so far with the Maxxforce 7? Any issues? we are looking to purchase a serrano also here next week.

thanks
manny

Only drove it home so far and a couple of times locally but impressed so far. Feel free to call me, 316-650-9593. Late is Ok, we are night owls.

Hork · 12-05-2020, 09:07 AM

Quote:

Originally Posted by Freddyjoe

Bought it at 28K miles, and now at 52K...

Never had problems, run smooth and very efficient. My mecanics told me to change oil every 5k miles or more often and that is what I go with.

We really like it.

Freddy!! You are the first one I have seen with a 34M, not very common. There were 2 nationwide for sale when I bought mine, haven’t seen one since. Hey I may need help since we are new but first question: There are 5 lighting switches (I think) in the back bedroom, righthand wall facing and underneath the TV. There is a row of 3 and then mine has a row of 2 right under those. Those 2 don’t seem to do anything. What are they for/to? Headed to Elkhart next week for renovations so I can get fixed if I knew what they are for. Thanks!!!

Freddyjoe · 12-05-2020, 05:17 PM

Quote:

Originally Posted by Hork

Freddy!! You are the first one I have seen with a 34M, not very common. There were 2 nationwide for sale when I bought mine, haven’t seen one since. Hey I may need help since we are new but first question: There are 5 lighting switches (I think) in the back bedroom, righthand wall facing and underneath the TV. There is a row of 3 and then mine has a row of 2 right under those. Those 2 don’t seem to do anything. What are they for/to? Headed to Elkhart next week for renovations so I can get fixed if I knew what they are for. Thanks!!!

I will to go check because it is stored for winter. We live up north in Canada. You can write me at freddyjoe1969@gmail.com.

Hork · 12-08-2020, 08:14 PM

Quote:

Originally Posted by Freddyjoe

I will to go check because it is stored for winter. We live up north in Canada. You can write me at freddyjoe1969@gmail.com.

Hello again!

Tried writing you but comes back as invalid email address.

Freddyjoe · 12-09-2020, 12:00 PM

Quote:

Originally Posted by Hork

Hello again!

Tried writing you but comes back as invalid email address.

The email address is ok...!! freddyjoe1969@gmail.com

Lumpysgirl · 04-27-2021, 06:43 PM

We have an allegro tiffin breeze, 2014, 28 feet, runs great except same thing black smoke a bit comes out when we accelerate. What is this and how do we fix?

vnorvi · 04-28-2021, 04:13 PM

Quote:

Originally Posted by ron55

Lookin to buy a nexus rv with international 7 engine
How are the newer max force 7 engines doing?
Are they as good or trouble free as the cummins? THANKS FOR ANY INFO

We had our Serrano for about 10 yrs and 30k miles. They have a bad reputation, which results in a good price in the RV. The reason they have a bad reputation, however, is because of a) the general relationship to the Ford engines. But these engines have nothing to do with the Ford engines, and b) you will commonly read about the turbo inlet tube popping of. It did with ours, and will will every one. BUT there is a simple preventative measure. You either get the update kit from international (basically a more robust clamp that looks like a radiator hose clamp) or b) buy a bigger clamp. In either case drilling though the clamp and putting in a metal screw. Problem solved.

But note. The oil filter is hard to get to without removing the clamp. You have to really push the oil change people to tighten the clamp down well: if you do not, they will not, and the clamp will pop off . For sure. . Better yet, pop off the engine cover and just tighten it yourself after every oil change.

Once we this we never had a hiccup.