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Topic: ISM450 & Other U320 Big Ticket Service Items? (Read 655 times) previous topic - next topic

ISM450 & Other U320 Big Ticket Service Items?

Knock on wood, I have not had any troubles with my ISM450 since purchasing in 2016.  I've logged probably 15-18000 miles and only performed fluid and filter maintenance.  I have no indication that anything is not working correctly, but I have a trip to Idaho in June, and I want to get some of the big ticket items scheduled and out of the way.  My plan is to have the valves adjusted and the injectors serviced, and I will also have the Meritor disc brakes serviced by the professionals.  I may not be using the correct terminology for the injector work, but I recall there being some kind of injector work listed on the FT service schedule.....  Are there any other items it would be worth paying the shop to test or look at?  Turbo?  Is there any kind of test that can be done to make sure it is working properly?  My coach does not have a boost gauge or EGT gauge/pyro.  Again, I have no indication it is not working properly, but if there is some easy test or PM that can be done to ensure longevity, seems like it would be money well spent.  Not looking to spend money just on account of cause, but interested in what more experienced owners suggest I look into.

The Allison trans has been serviced and has TranSynd in it.  Rear diff has been serviced.  I'm pretty sure they did the fluid in the front hubs when the trans was serviced, I will have to pull my service records and check.  I do all my own chassis greasing (except for the brakes) so that's good.  I recently did the hydraulic fluid and filter so thats good.  I'm going to install a FASS fuel filtration system and lift pump (in hand already) and will likely do the fuel lines at the same time just so they are done and off the list of potential issue points.  I'll do the air drier myself.  Coolant flush & replacement was done in 2017 upon initial servicing.

Any recommendations on things I missed?

Re: ISM450 & Other U320 Big Ticket Service Items?

Reply #1 –
When servicing disc brakes, be sure helper springs from Meritor on all slide pins

Re: ISM450 & Other U320 Big Ticket Service Items?

Reply #2 –
Quote from: Rudy –
When servicing disc brakes, be sure helper springs from Meritor on all slide pins

This is an addition to the existing brake system/component, maybe offered as an aftermarket or after manufacturing upgrade from Meritor?  Or are you just suggesting to check that they are still present?

The brakes on this thing are impressive and work well in conjunction with the transmission retarder. 

Re: ISM450 & Other U320 Big Ticket Service Items?

Reply #3 –
The springs are an upgrade recommended by Meritor. A Meritor part not after market.

Re: ISM450 & Other U320 Big Ticket Service Items?

Reply #4 –
Quote from: craneman –
The springs are an upgrade recommended by Meritor. A Meritor part not after market.

I will check to see if I already have them, and if not, I will procure before taking the coach in for the work and ask them to install.

Re: ISM450 & Other U320 Big Ticket Service Items?

Reply #5 –
I suggest checking the following for any signs of leaks:
1) Radiator and adjacent components
2) Steering gear box
3) Hydraulic pump
4) Shocks

as well as...

5) Ride-heigh control valve linkages (in particular the rubber components that connect them)
6) The weld on the backside of the transmission retarder bracket if not already reinforced
7) Confirm functionality of the dometic thermostat before taking off (they're at the age where they're dying)

Re: ISM450 & Other U320 Big Ticket Service Items?

Reply #6 –
Quote from: Elliott –
I suggest checking the following for any signs of leaks:
1) Radiator and adjacent components
2) Steering gear box
3) Hydraulic pump
4) Shocks

as well as...

5) Ride-height control valve linkages (in particular the rubber components that connect them)
6) The weld on the backside of the transmission retarder bracket if not already reinforced
7) Confirm functionality of the dometic thermostat before taking off (they're at the age where they're dying)

1) radiator IS leaking, just noticed sunday upon returning from a trip to the desert.  Its on the list, but something I will self perform. 
2)  dry
3)  dry - I have lightly browsed that thread about the broken pump shafts, not sure if that applies to the 450 engine....will have to do more reading when i have the time.
4) Koni's were installed along with new bags back in 2018.  Probably 10-12k miles on suspension
5) Have never done, will add to the list thank you.
6) did reinforcing weld in 2022 prior to my last trip to Idaho
7) Have the 10 button dometic and have never had an issue.  Heat/Aqua Hot function as they should.  I serviced the Auquahot in 2021.  I do have a non functioning roof top unit/AC, but I don't have any issues with sweating a little bit....

Thanks for the input Elliott.

Re: ISM450 & Other U320 Big Ticket Service Items?

Reply #7 –
Quote from: Rudy –
When servicing disc brakes, be sure helper springs from Meritor on all slide pins

And replace any slide pins that have significant corrosion/pitting (they should pull them to check).

Regarding valve/injector adjustment - how many miles on the coach and has it ever been done?  Foretravel's service schedule for that (plus the diff fluid change as well as transmission fluid change if you're running Transynd) is ridiculously excessive IIRC.

Re: ISM450 & Other U320 Big Ticket Service Items?

Reply #8 –
Quote from: Michelle –
And replace any slide pins that have significant corrosion/pitting (they should pull them to check).

Regarding valve/injector adjustment - how many miles on the coach and has it ever been done?  Foretravel's service schedule for that (plus the diff fluid change as well as transmission fluid change if you're running Transynd) is ridiculously excessive IIRC.

Well, the coach came with very little service history.....I know, many would walk away from a no history unit.  I also didn't pay for a PPI.  Long story short, I believe I am around 114k or so total miles (there was a documented ODO change around 89k and I think I just clicked 25k on the new ODO this weekend), so if it never had the valve or injectors serviced, its definitely time to finally baseline those.  I suspect it has been done, as who would buy a $400k coach, put 95k on it and do zero recommended servicing?  I'm sure strange things have happened...

Re: ISM450 & Other U320 Big Ticket Service Items?

Reply #9 –
Quote from: evantwheeler –
Well, the coach came with very little service history.....I know, many would walk away from a no history unit.  I also didn't pay for a PPI.  Long story short, I believe I am around 114k or so total miles (there was a documented ODO change around 89k and I think I just clicked 25k on the new ODO this weekend), so if it never had the valve or injectors serviced, its definitely time to finally baseline those.  I suspect it has been done, as who would buy a $400k coach, put 95k on it and do zero recommended servicing?  I'm sure strange things have happened...

I believe the Cummins-recommended interval for valve/injector adjustment is around 90-100K miles, so yes, there is a good chance it had not been done (and likely wouldn't have needed it, anyway).

As I'd mentioned, Foretravel's recommended service interval (15K, IIRC), is extremely excessive.  Ditto their 12k mile/annual differential fluid change.  A switch to synthetic there is almost a "once and done". 
 

Re: ISM450 & Other U320 Big Ticket Service Items?

Reply #10 –
Quote from: Michelle –
I believe the Cummins-recommended interval for valve/injector adjustment is around 90-100K miles, so yes, there is a good chance it had not been done (and likely wouldn't have needed it, anyway).

As I'd mentioned, Foretravel's recommended service interval (15K, IIRC), is extremely excessive.  Ditto their 12k mile/annual differential fluid change.  A switch to synthetic there is almost a "once and done".

100k is what I recall seeing in the cummins literature or on the forum for the valve adjustment so it's been on my mind, it just hasn't made the priority list.  I agree on the other service intervals, I have no plans to do the trans or diff again for a LONG time. 

Thanks for your input.