PM On 20 Yr Old Coach

[CVD]

Went to Pomona RV show today. Saw lots of interesting coaches (big and small, expensive and less so). We came home, thought for a while, and decided what we have is fine for another year or two. So, I’m wondering what sort of additional preventive maintenance I should consider on my coach of 12 years.

Background

• Coach: 1999 Freightliner XC chassis (23,600 GVW), ISB 275 hp engine, MT643 trans; 75k miles (3 – 4 k miles per year). I know mileage is not an issue, but years might be.
  
• 
  Fluids: I change oil/filter and lube all fittings every 24 months. Coolant and trans fluid was changed 6 – 7 years ago (~20k miles ago). Hydraulic fluid has not been changed.
  
• 
  Engine – The only significant problems in 12 yrs have been a bad starter, cracked exhaust manifold, and leaking heater core. I’ve changed the fan belt, have not changed hoses.
  It smokes for a second or two upon cold start up. I’ve been told it’d due to leaky injectors, but to wait until it gets worse before doing a $1,500 injector replacement service. Otherwise, it runs fine, still get’s 10 – 11 mpg (not towing).
  BTW – this is a “Code 53” engine, no cracks in block, no coolant loss (has been pressure tested to confirm).
  
• 
  Tires – replaced 4 years ago.
  
• 
  Brakes – no maintenance has been performed. (plenty of pad remaining)
  
• 
  Air system – have had cracks in air bags for years, but haven’t changed them or air lines. Air dryer has been serviced twice.
  
• 
  Generator – 6500 Onan LP unit. Runs fine, only 250 hours, is “exercised” regularly.

Question
Now that it’s approaching 20 yrs old, anything else I should be doing to prep it for a couple 1,000 mile trips over the next year or two?

[ncrowley]

Looking at your list, there are maintenance items that I do not see there. For example, the air dryer. Have you replaced the filter? Have you replaced the hoses in the generator? There are other generator maintenance items. Have you lubes the pac brake? I have a spreadsheet with all the maintenance items and how often they should be done that I can email you if you send me a private message with your email address.

[Bill_Satellite]

I don't do any different PM on my 29 year old coach than I did when I bought it at 11 years old which was the same as was done when it was new.
I disagree on changing the oil every 24 months as my engine manufacturers guidelines are 15,000 miles or every 12 months.

[John_Joey]

At 20 years on a well maintained coach I think your biggest issue will be corrosion. From electrical connections, to mechanical connections (i.e. wire to heater gate valve), to dried out furnace bearings, to worn out shock gourmets, to rusted out hose clamps.

All the things you fix when you're on the road and they go out because they are being used/pushed and not just sitting idly in a driveway.

Bring the toolkit, volt meter, lubes, duct tape/wire and fuel up and go.

[T18skyguy]

Definitely change those hoses. They go bad from the inside out. They have a tendency to go at the worst possible time, like when on a remote mountain a zillion miles from any parts store. Otherwise, your doing a lot of good things.

[jplante4]

I went completely through the suspension last winter. Freed up all the stuck zerk fittings, replaces front and rear sway bar bushings and a bunch or other rubber parts. Big difference in the ride.

The previous fall I had the local CAT shop do the 100,000 miles valve lash adjustment.

Last spring I replaced the house and chassis batteries and added another 100 watts of solar.

Looking into the future...

Clean out and re-brush the Onan 6500

Give the radiator and CAC a thorough cleaning. I just sprayed it out last spring. Need to shoot some Simple Green Extreme in there.

I'm sure the fuel pump will need replacing soon. I can't decide if I wait for it to give up or if I do a preemptive strike.

[rgatijnet1]

All parts of the suspension, especially any rubber bushings/bumpers as well as any belts and hoses. Also you want to check flexible rubber brake lines and inspect steel brake lines for rust.