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Topic: ECM Mileage vs Dash Mileage (Read 1473 times) previous topic - next topic

ECM Mileage vs Dash Mileage

My dash indicates about 70k miles on the coach. My silverleaf indicates about double that. So either the gauge on the dash  quit working for a while, or perhaps  I got a refurbished ECM at some point? When I got the coach, it was already on at least it's second set of airbags and I think shocks, and one of the AC units had been replaced, so I suspect it probably was more of a "user" than I originally thought. Just curious what others have seen in this regard. What do you think is more likely the correct mileage? Dash or silver leaf?
1987 Grand Villa ORED
2001 U320 4010

Not all that wander are lost... but I often am.

Re: ECM Mileage vs Dash Mileage

Reply #1 –
I had to replace both the speedometer and tach gauges due to being unable to read. I had the correct hours put on the new tach but wanted to quickly see the miles I had put on the coach so had it start at zero. I would believe the engine ecm to be correct. I would let any buyer see the true mileage on the VSMpc before a sale if I ever sell the coach.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: ECM Mileage vs Dash Mileage

Reply #2 –
On our coach the speedo was replaced as it went to Canada and needed to show KPH.

Our coach has logged just over 160,000 miles per the ECM via vmspc. So it has been on the move.

We use it on a week long trip every month in the summer and go south to Arizona from Oct/Nov till March.

I would trust the ECM over the dash simply because it's easy to replace the speedometer.

I have been surprised at how accurate the speedo is. The dash, vmspc and garmin gps all read exactly the same speed.
Jerry & Nona and Kimeru the cat that thinks she's a dog
1998 36' WTFE U320  #5314 Motorcade #17711
USAF 1975-1995
2019 Subaru Crosstrek 'toad'
2003 Subaru Legacy touring car
jerry Fincher | Flickr

Re: ECM Mileage vs Dash Mileage

Reply #3 –
I would say Silverleaf.  That is unless the ECM was replaced with a used ECM at one point in time, which is possible.  The speedometer can be changed out.  The one that was in my 1997 died before I sold the coach and the new one only showed the mileage since I replaced it.

In Texas you have to put down what the real mileage of the vehicle you are selling or note that you do not know.  The problem comes in is if an earlier owner sold the coach and did not notify correctly the person they sold to. 
2014 ih45  (4th Foretravel owned)
 1997 36' U295 Sold in 2020, owned for 19 years
  U240 36' Sold to insurance company after melting in garage fire
    33' Foretravel on Dodge Chassis  Sold very long time ago

Re: ECM Mileage vs Dash Mileage

Reply #4 –
Mine has a replacement ECM. OBD2 shows like 895k

Re: ECM Mileage vs Dash Mileage

Reply #5 –
When we purchased ours we were told there was around 180k miles on it. The dash said 45k miles. There was a sticker under the driver window that said "mileage not accurate" or something along those lines. Once I got vmspc up and running, the ecm read out 117k miles. Since the silver leaf wasn't originally hooked up correctly, (would not show mileage until I cut some wires) I figured the speedometer was changed prior to the previous owner and somehow numbers got mixed up.

I'm going with what the ecm is showing as my mileage.
1999 U320 WTFE #5586
2014 Subaru Forester 6sp
4000 watts of solar
650 aH @ 24v

Re: ECM Mileage vs Dash Mileage

Reply #6 –
When I purchased my rig, the odo gauge was dim at best and I could not make out the mileage. When I got the Silverleaf shortly thereafter, I could see it was off a few hundred miles. Since then, it has grown brighter at times and I am off about 6-700 miles. I go by the ECU. It's still on the "to fix" list but lower priority since I have the Silverleaf.

You can also compare PO records if available and even run a carfax to confirm miles, I did both.
Jason
2000 U295 36' Non-slide  ISC350

Re: ECM Mileage vs Dash Mileage

Reply #7 –
Our Prolink 9000 gives us gallons used down to a tenth used since new, total miles, trip mileage, real time mileage, plus dozens engine info, injector testing, PTO, no smoke setting, fuel temp. etc.

Speedo/ODO info is not that reliable as it has quit for part of trips. We have a GPS speedo now. The receiver overheated in the sun for one trip so the speedo quit for a while.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: ECM Mileage vs Dash Mileage

Reply #8 –
How do you get to the ECM indicator to compare? I have only used the trans indicator for oil levels etc
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: ECM Mileage vs Dash Mileage

Reply #9 –
Quote from: dicksop –
How do you get to the ECM indicator to compare? I have only used the trans indicator for oil levels etc
You read on your obd2 reader for your coach

Re: ECM Mileage vs Dash Mileage

Reply #10 –
Not speaking fluent coach language...obd2 is what?
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: ECM Mileage vs Dash Mileage

Reply #11 –
Is it possible to reconcile the ECM s/n to the engine s/n to determine if the ECM has been replaced?
Tim Dianics
Pam Sapienza
Vader PupZilla Labrador Canine Beast (AKA Pup)
Columbia, MO
1996 U320 4000
2021 Jeep Gladiator, Diesel

Re: ECM Mileage vs Dash Mileage

Reply #12 –
Peter you use a scan tool
Rick & Hilda looking forward to full- timing one day for now couple of months at a time
1999 U270 3602
Built number  5530.  Feb 1999            Motorcade  number 18438
8.3 Cummins Allison six speed with brake  retarder
Purchased Nov 28 2019

Re: ECM Mileage vs Dash Mileage

Reply #13 –
First, you have to have an electronic coach with an ECM. If you have one, check under the dash next to the driver's left knee for a OBD (on board diagnostic) port. It may have a cover on it. You then need to identify they type of port you have by comparing it to what is online. Some coaches may have two ports, one for the engine and one for the transmission. Shop around for the adapter you need as prices vary a lot. They should be inexpensive.

Readers (can't make any changes or Tools (Pro Link as an example) will have a site showing what they can do and  come with and what is required for your engine.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: ECM Mileage vs Dash Mileage

Reply #14 –
Quote from: Pierce & Gaylie Stewart –
First, you have to have an electronic coach with an ECM. If you have one, check under the dash next to the driver's left knee for a OBD (on board diagnostic) port. It may have a cover on it. You then need to identify they type of port you have by comparing it to what is online. Some coaches may have two ports, one for the engine and one for the transmission. Shop around for the adapter you need as prices vary a lot. They should be inexpensive.

Readers (can't make any changes or Tools (Pro Link as an example) will have a site showing what they can do and  come with and what is required for your engine.

Pierce

Fairly sure these things have a J1939 Cummins diagnostic port rather than an OBD port. It looks like they do make adapters, but not sure if/how they work.
1999 U320 WTFE #5586
2014 Subaru Forester 6sp
4000 watts of solar
650 aH @ 24v
 

Re: ECM Mileage vs Dash Mileage

Reply #15 –
The 1939 adapter is  sort of like the plug adapters you buy when traveling overseas. The J1939 allows the reader or tool to communicate with the ECU. The price is about $25 so not going to break the bank. The most popular for RV owners is a laptop with software  translating the information into something we can read and understand.

You can find exactly how to do it from other Foreforum members and may be able to purchase everything from Roger Engdahl if he still is in the business. Nice to have a glass dashboard with digital gauges in front of you

All U300s with 2 cycle engines will have a DDEC II ECU that can be read by a Wanderlodge member's software via Bluetooth on a tablet or read and make some tests and changes with the Pro-Link tool and the correct cartrige that fits in the back of the tool.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)