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bluwtr49's avatar
bluwtr49
Explorer II
Apr 29, 2015

Oil Analysis Questions

When we bought our current coach last Sept the PO stated the engine oil was changed "recently" but the coach had very little use for a couple of years. Last month I had the tranny oil changed and both the engine and tranny (before changing) fluids sent out for analysis.

Both came back with excellent results but I've decided to start an annual fluids sampling program but I'm unclear as to exactly what to do with the information or how to compare it to history or standards. I suspect for the engine, it can help clarify just when the oil needs to be changed. Using the Cat procedure for hours and load, that would equate to once every 4 years based on my driving....seems to long but yearly seems to short.

Right now I'm leaning towards JG for the sampling but they over 3 services and I'm unclear which I should use.

My engine is a Cat C-12 505 HP 36 qt sump.
The Tranny is an Allsion 4000 with the shallow sump and Transynd
Both have 91,000 miles.

Any clarification and info from others on a sampling program would be much appreciated.
Class A

7 Replies

  • Dale_Traveling's avatar
    Dale_Traveling
    Explorer II
    Apr 29, 2015
    I haven't moved up into the diesel world, yet, but I send out an sample with every 5000 mile oil change. I want the trend data so I can catch problems early and take whatever steps possible to correct. Plus when the day comes that I sell the coach I've got one more piece of document evidence concerning regular maintenance for a prospective owner to look at. I'm about to send out a transmission oil sample to see if I can go a bit further before needing to change that oil.
  • bluwtr49's avatar
    bluwtr49
    Explorer II
    Apr 29, 2015
    Thanks for the replies and I like the Cat program recommendation. I'll look into that since the one analysis I have was done by Cat.

    According to the maintenance manual on the C-12 it looks like the recommended oil change interval (light duty) is about 23,000 miles but that is for continuous operation I don't believe it's completely correct for a MH that does ~6K/year. I've never seen a 5K change interval mentioned by Cat.

    The tranny is easy, every 4 years or 300,000 miles or so.

    I'm still curious about how others use the info on the analysis.
  • dodge_guy's avatar
    dodge_guy
    Explorer II
    Apr 29, 2015
    I know you want input from others that use oil analysis, but if you just keep up with the maintenance you won`t need to ever do an Oil Analysis.
  • JR45's avatar
    JR45
    Explorer
    Apr 29, 2015
    I use Cat SOS sampling from Peterson Cat sent to Eugene, Or at a cost of $13.25per sample. Takes about 4 days to get an email back and 6 to 7 days to get a the paper work. One thing about the cat motor is they have a Heui pump and the injectors need clean oil and fuel. Use only Cat Advanced High Efficiency Engine Oil Filters 1R-1808 same with fuel filters. The max is 5000mi on an oil change the way the injectors shear the oil because they are oil fired, they need 500lbs of oil pressure inside the injector to fire and changed once a year.
    JR
  • Ductape's avatar
    Ductape
    Explorer
    Apr 29, 2015
    Trust the lab to tell you when something needs to happen. They see more samples in one day than we will in a lifetime. If you really want to get into the science, then go to Bob is the Oil Guy.

    BITOG
  • tinkerer's avatar
    tinkerer
    Explorer
    Apr 29, 2015
    We use the Cat SOS oil sampling program. You get signed up to their program and they will e-mail you the results with comments. They charge us $11.00 per sample.:)
  • Bill___Kate's avatar
    Bill___Kate
    Explorer
    Apr 29, 2015
    We have been using Blackstone Labs
    . They seem reasonably priced, send/email you a nice report, and maintain a database of your data.

    They also sell a nice little sampling pump for taking samples directly into their sample bottle.

    We don't run that many miles either, but I send an engine oil sample before each change, and a tranny sample every other year.

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