Is My Motor Home Safe To Drive

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psmithsr

Member
Joined
May 6, 2012
Posts
7
I have a 1999 Foretravel with an 6 speed Allison transmission with retarder.

A recent check using the "electronic dipstick" found the Transynd was
6 quarts low.  The steel dipstick found the Transynd was 1/8 inch
below the "Hot" line (when the oil is cool).  Someone
suggested the electronic dipstick calibrates the steel dipstick. If
so, this could mean it's OK if the oil is at the "Hot" line when cool.
Not sure if you agree.

I added 1 quart and the electronic dipstick found the Transynd was 5
quarts low.  So far so good.

So I added a second quart.  The electronic dipstick found the Transynd
was 6 quarts low!  Since I was at a different location I thought the
coach might not be as level as before and the 6 quarts low was an
anomaly. So I added a third quart and the electronic dipstick again
found the Transynd was 6 quarts low.  So I stopped adding Transynd
until I could determine what is going on.

The steel dipstick now finds the Transyn is at or a little above the
Hot line (when the oil is cool).

Two days after I wrote the above history it hit me.

The only consistent player in this drama is the steel dipstick.  After
I added 3 quarts it said the oil level has risen.  This could be
because both readings of the dipstick were made at the same level RV
Site.

It also suggests the culprit is the electronic dipstick.  It
apparently doesn't know dip from stick ;o)

Now I've never had a problem of the tranny running hot.  The questions
are: Is there too much oil in the tranny, too little oil in the
tranny, and is it safe to drive?

For this transmission I believe full is 28 quarts.

Assuming it is 3 quarts overfilled, is it safe to drive?

best, paul
 
My first suggestion would be not to drive it overfull. That is asking for trouble but first you have to determine what the proper level is.
The electronic will only work properly if the rig is level (look at your levels in the MH) and the oil is up to operating temp. So you warm it up, make sure you are reasonably level and then use the electronic to see what the level is. Normally the electronic level is more accurate and the stick is for a general guideline but that does not mean your electronic is working properly.
You don?t say if this is a new to you MH or what model trans. Mine is a MD3000MH with 4? sump and holds 22 qts of Transynd. You can find your model on the tag on the side of the trans.
Either call or use Allison?s website to see what your capacity is, Allison Customer Service 800-524-2303.
I would just service it if it is new to you. Drain, do filters & add the appropriate amount of fluid, check to see if the electronic agrees then mark your dipstick so you know. This would be the most exact method but not the cheapest. It is really the only way to know for sure how much fluid is actually in the trans. if you can?t trust the stick or level indicator. Hope it helps.
 
I heard of a similar case when I attended "Camp Freightliner" a few years ago from Mike Cody, the instructor. Another owner had went through pretty much the same routine you did before he called Mike and discussed it with him. What the guy was seeing was not a low fluid warning, but a code that indicated that the tranny temp was too low for the electronic diagnostics to work. Mike advised do NOT drive the vehicle over filled as damage to the trans may occur. Instead drain out the extra fluid and recheck the fluid levels with the trans at the proper temp.
 
Sarge is almost surely right abut what is happening. It is all too easy to read the electronic "too cool to test" for "6 qt Lo".  I know - I've done it myself and was in a panic until I figured out that i was reading it wrong. Re-read the Allsion instructions again and pay very close attention to what the display is telling you.

Allison will tell you straight out that the electronic report is the only accurate one and to ignore the dipstick. The external dipstick is fabricated and installed by the chassis builder and totally dependent on how the tube was installed and the length of the dipstick. It is not at all reliable. No part of the external dipstick is supplied or calibrated by Allison.

As for driving with it overfull, it is hard to say. Obviously it is not advised, but there seems to be no data on just how risky it is. Shouldn't be all that hard to drain some out, though on my 3000MH there is no obvious drain plug among the dozen near-identical bolt heads on the tranny pan. If you can't figure out the drain, you could try pulling the filters. That usually loses about two quarts. You might be due for a filter change anyway!

As fo
 
My understanding is the electronic dipstick needs 140 degrees or higher.  Mine have always been at 155 degrees or higher.

Anyone have any luck pumping oil out of the transmission.  Through the dipstick tube?

best, paul
 
I bought a small hand pump at Wal-Mart in the boating dept. to fill the lower unit gear oil for my outboard motor. I would assume with a proper length of small vinyl hose you could pump it out through the dipstick tube. I caught mine on clearance in winter for only a few bucks, full price I think it was still fairly inexpensive.
 
Dion International Truck in an Diego is an authorized Allison service center.

They returned my call today.  They recommended against driving with oil too high because it can lead to frothing.

They also recommend against relying on the electronic dipstick.  They do recommend relying on the steel dipstick, once you've "calibrated it" to know where full is on that particular dipstick.

best, paul
 
They do recommend relying on the steel dipstick, once you've "calibrated it" to know where full is on that particular dipstick.

Sure, and you calibrate it by comparing to the electronic dipstick. Duh!

Old mechanics never trust new methods.  ::)
 
FWIW our Allison (MH3000?) has a second steel dipstick, accessible from below. Last time I had the coach serviced by a mobile guy I was parked at an RV resort and had forgotten to check the fluid electronically when we'd parked a week earlier. (More correctly, my driver doesn't think of doing it and, once she's pulled the coach into a site, she shuts the engine down to minimize disturbance to neighbors.)

The 'primary' steel dipstick is in the rear closet, and I have to remove storage drawers I previously installed in order to get to the hatch. That's when the tech told me "no  problem, I'll check it using the other steel dipstick while I'm under the coach".
 
Technically the stick and electronic check will be calibrated to one another, if done according to specs. Some like to calibrate the stick with cold oil and is why I thought you might be having some trouble. ( Old mechanics never trust new methods. LOL ) When at running temp you should use the electronic and it will always be more accurate as it compensates for the temp of the oil so you don?t have to get the trans at one certain temp. like the old days. Back before electronic levels we used two different sticks but for the same purpose, depending on temp.
If you check the stick hot it could be off depending on who calibrated. If you check the electronic cold, it WILL be off. Doesn?t matter what codes or level it says, electronic is wrong until running temp.
Usually, after servicing you check the stick at oper temp and verify the mark. Then you check electronic and it should say OK.
If the stick and electronic don?t agree then the stick might have been calibrated cold. You have to start with what you know and follow it through or just take it to a shop. That is why I suggested a service, on level ground, then you know what you are starting with. You never said if this MH was new to you or any history on it so I?m just guessing though as there are many variables.
Gary, your 3000MH should have a recessed round plug with a hex in it for removal, 3/8? square drive.
 
No short dipsticks on my HD4060R

But after 2 weeks or wondering, a Jabsco 17850-1012 Premium pump, a gallon of Transynd, tubing, and more than $200 I'm happy (; to report we're back where we started: 1/8 inch below "hot" on the dipstick.  And the question remains: Is that full, low, high, or what?

The electronic dipstick is clearly not working correctly.

Thanks for all the suggestions.

best, paul
 
I had the Transynd put in almost 2 years ago.

All readings were at the temp recommended for the device: 155 or more for the electronic dipstick, "cold" (it's 100 here in El Centro today) for the steel dipstick.

At temperature, and at the same RV Site, with the coach at the same HWH level, the electronic dipstick had 6 quarts low, then 5 quarts low after I added a quart, then 6 quarts low after I added a second quart, then 6 quarts low after I added a third quart.  Not only not consistent. Not rational.

Also at the same RV Site, the steel dipstick was consistent.  !/8 inch below "hot" and then 1/4 inch above "hot" after 3 quarts.

Then tech at Dion Intl Truck thought I should have the electronic dipstick looked into.

Right now, it would be nice to find a way to determine when my tranny is actually full that doesn't involve an oil change.

best, paul
 
At temperature, and at the same RV Site, with the coach at the same HWH level, the electronic dipstick had 6 quarts low, then 5 quarts low after I added a quart, then 6 quarts low after I added a second quart, then 6 quarts low after I added a third quart.  Not only not consistent. Not rational.

Paul, sounds like you are doing it at correct temp on level ground so I would agree the sensor is prob going bad. The first thing I noticed above is the max reading for low oil is usually 3 qts, if your sure yours is saying 6 something is still wrong.
The 4060 is the large box so depending on your sump you are well over 30 qts for an oil  change. I thought your stick would have a range (hot high & low), not just a hot mark. From what you are saying it was 1/8? below the hot mark at running temp. Do this check a couple different times at least, to validate the same reading and if it agrees then you are good to go.
If it does not come up at the same reading consistently on the stick then pull your vent and clean it. If the vent is plugged it will give erratic readings on both the stick and sensor.
If the stick level checks out ok then I would definitely have the shop check - change the level sensor, its towards the rear of the trans accessible from the sump. I don?t think it would be a bad job but can?t say for sure because I have not done one myself. You can have them check stick calibration at same time and verify it before you leave with the MH. Keep us posted.
 
No, it was 1/8 inch below the "Hot" mark with oil at cold temp, not hot temp.

best, paul
 
No, it was 1/8 inch below the "Hot" mark with oil at cold temp, not hot temp.

Then warm it up like you were going to use the electronic, only check the stick instead. Do this a couple times to verify.
I agree you will be overfull when the oil is hot. Drain out what you need to before you drive it.
 
I've had this motor home for more than 2 years now and have put quite a few miles on it and had no problem with the transmission.  I had the Transynd put in and driven with oil at 1/8 inch below the so-called "Hot" mark for quite a few miles.

It's hard for me to believe it is overfull now.  From what Dion Intl told me, an over full condition will create a lot of problems.

What's need is an Allison shop to fix the electronic dipstick, which is what Dion Intl Truck recommended.  That will establish the correct hot oil level on the steel dipstick.

best, paul

 
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