Lost 3 gallons from Tranny, am I screwed

[jacwjames]

Best I could do was Valvoline Dexron III.  

I plan on doing a service when/if I get home. 

[96 EVO]

3 minutes ago, tmw188 said:

Jim, were you able to find some Transynd or did you just add some Dextron for now? Just curious. 

Here......

https://www.allisontransmission.com/parts-service/approved-fluids/on-highway-fluids

Take your pick!

Castrol is only one of many!

[tmw188]

7 minutes ago, jacwjames said:

Best I could do was Valvoline Dexron III.  

I plan on doing a service when/if I get home. 

Do you think you could sneak in a change at a CG or somewhere else if you could pick some up on the rd? Maybe give Tom at JG a call for his thoughts on changing it now or when you get home. You might not know he was instrumental in the 295 spec. This has got to be driving you crazy, but I would think you’ll be fine. 

[dl_racing427]

Jim,

Since the tranny didn't slip or display other operational defects, it's likely you never lost pressure and there's no damage.
Even if it had slipped a bit, damage wouldn't be instantaneous.

I wouldn't be concerned driving it home, and a oil and filter change should put you back in top shape.

I'm particularly interested in the cooler failure, and it's probable cause.
Derale is a major cooler supplier, and I'd be surprised if they don't stand behind their product.

Edited October 13, 2023 by dl_racing427

[Ivan K]

As far as Dexron, it was our factory fill and I did not switch to Transynd until 150k. Now at over 200k still no problems (hope not to jinx it), I would not worry until you can switch again.

[96 EVO]

5 minutes ago, Ivan K said:

As far as Dexron, it was our factory fill and I did not switch to Transynd until 150k. Now at over 200k still no problems (hope not to jinx it), I would not worry until you can switch again.

Replaced my 'factory' fill a couple of weeks ago (56,000mi)

Not a fleck of metal on the magnet, or in the pleats of the filters 👍!

I think when the rest of the coach dies, I'll shoehorn this tranny into my KIA SUV 🤔!

[jacwjames]

1 hour ago, 96 EVO said:

Replaced my 'factory' fill a couple of weeks ago (56,000mi)

Not a fleck of metal on the magnet, or in the pleats of the filters 👍!

I think when the rest of the coach dies, I'll shoehorn this tranny into my KIA SUV 🤔!

With good maintenance the Allison is a very good transmission. 

But running one low on oil can't be good.  The Allison shop said if it didn't suck air and show any signs of heating there's a good chance it will be OK

I've decided to head toward Zion National Park tomorrow.  I'll monitor temps and shifting performance.  If any doubt I'll head on down to St George UT which is the nearest Allison shop. 

I've got ~127K on my rig. 

[Ivan K]

Are you going all around to west entrance or through the tunnel? 

[Dr4Film]

Jim,

What was the reason for the leak at the return line in the new cooler you had installed?

Or are you waiting to get back home to figure out what happened?

[jacwjames]

9 hours ago, Ivan K said:

Are you going all around to west entrance or through the tunnel? 

No idea, I read about the tunnel yesterday and will probably try to avoid it. 

2 hours ago, Dr4Film said:

Jim,

What was the reason for the leak at the return line in the new cooler you had installed?

Or are you waiting to get back home to figure out what happened?

Richard,

It looks like the leak is coming from where the output fitting is attached to the cooler body, hard to see but I suspect it is a failed weld/solder/pressed fit.  I can't tell how the fitting is attached.  But for the time being I'm not going to fool with it.  I was able to use a Street L & 90 & two 3/4" male to #12 JIC male to be able to bypass the cooler. 

Attached is a picture of the cooler lower port where it was leaking, the fitting is out as I took it to town to try and match threads but you can see where the hydraulic hose is sitting, there was no stress on the cooler fitting.

Alao a picture of how I bypassed.  I knew I couldn't use a union because of the way the hoses were oriented and knew it would have been difficult (if not impossible) to bend/twist the hoses to use a simple union so I may a "U" with the Street L & 90  degree 3/4 inch fittings.  Worked out better then I expected. 

[Guest Ray Davis]

3 gals should make an awful mess, has that been mentioned?     If the leak was mostly at low speed I imagine the mess would be far less.

Anyway, slipping clutches are the real concern IMHO which would raise the temp greatly and rapidly destroy the clutches.  In yrs past you could smell burned tranny fluid & see a dark color but with Transynd I don't know.   

How about it Jim,  did you have oil everywhere?  The pictures above look amazingly clean.

Personally, I think you're ok, lucky but ok.

[jacwjames]

Well, I took off on I70 headed west, the first portion was mild grades and the temp hoovered at 160 then when I climbed the loooong grade up the pass after crossing the Green River it only got to 167.  Then drove another 130 miles with no sign of slipping, shifted good, when using the exhaust brake down and up shifted as it should.   

So based on that I think I'm OK.

I think the key to not having problems was that the last section of I70 before I exited was very flat so although I lost 3 gallons it wasn't low enough for the pickup tube to suck air.  If I would have been on steep grades it would have been a whole other story. 

Just lucky I decided to pull off into an exit that had a campground prior to driving toward Moab.  I did that just to top off my fuel and saw the campground.  If I would have kept going and took the exit directly toward Moab I would have lost more oil and there were grades on that route. 

[Guest Ray Davis]

I remember yrs ago ( 60 ) LOL transmissions had a vacuum device that controlled shifting.  This device could develop a hole in its diaphragm allowing it to suck fluid into the engine where it was burned.   I know we don't use the vacuum, but still, I wonder if there is any way for something similar to happen.     I learned some time ago that on some engines hydraulic fluid can cross over into the engine oil.   So I'm curious if there is any other way for the tranny fluid to escape without leaving a trace.

Edited October 13, 2023 by Ray Davis

[Ivan K]

46 minutes ago, Ray Davis said:

I remember yrs ago ( 60 ) LOL transmissions had a vacuum device that controlled shifting.  This device could develop a hole in its diaphragm allowing it to suck fluid into the engine where it was burned.   I know we don't use the vacuum, but still, I wonder if there is any way for something similar to happen.     I learned some time ago that on some engines hydraulic fluid can cross over into the engine oil.   So I'm curious if there is any other way for the tranny fluid to escape without leaving a trace.

Yeah, the vacuum modulator before computers took the shift point control over. But as far as I know, on these rigs the only possible ATF cross contamination would be in the radiator and that would be very noticeable with 3 gallons missing. Since Jim found the leak point, it is unlikely to have this much bad luck. 🤞

BTW,  I have similar cooler in the drag car and had a fitting come off of the aluminum exit line as well. Probably due to vibrations. Don't remember how the factory held the fitting on but certainly not well enough. In my case, JB weld fixed it.

[tmw188]

Did you notice inside the engine door or on the car for fluid residue?

[jacwjames]

58 minutes ago, tmw188 said:

Did you notice inside the engine door or on the car for fluid residue?

Yes I did but at the time I thought it was road oil, I went through a construction area that had big warning signs "Fresh Oil On Road".  I did look at the radiator and didn't see any signs of oil and none dripping. 

Didn't put 2 & 2 together until I found the cooler leaking. 

[96 EVO]

On 10/12/2023 at 10:34 AM, Ivan K said:

Fluid temp at least 160F, in neutral with engine running press UP and Down at the same time, once. It will start a countdown and tell you either OK or how much low/high. If you had a dipstick, it only is meant to check safe level after fluid change.

Ivan, I just took mine for it's first run since changing fluid & filters.

Stopped at a parking lot about 20mi from home, fluid temp 181F, level check showed 2 quarts low.

Drove home, trans now 195F, level check showed OL-OK.

I wouldn't trust it at 160F.

[Ivan K]

16 minutes ago, 96 EVO said:

Ivan, I just took mine for it's first run since changing fluid & filters.

Stopped at a parking lot about 20mi from home, fluid temp 181F, level check showed 2 quarts low.

Drove home, trans now 195F, level check showed OL-OK.

I wouldn't trust it at 160F.

Ha, yeah, ATF expands with temp significantly so it has to be meassured hot. I think 160F was the minimum for the system to even start. I suppose at you normal cruising temp would be the time to do it.

A quick look into the library says this: 

To ensure an accurate check, operate the transmission until the sump fluid

temperature is 160–200°F (71–93°C); converter-out temperature is

180–220°F (82–104°C).

[jacwjames]

I'd suggest that if when you check the oil level via the shift pad and it indicates you are 2 quarts low that you add 1 quart, drive and then check again.

When I did add the auxiliary cooler I lost ~1 quart when I removed the hose to the radiator.  I then calculated that the new hose and cooler held ~2 quarts.  So I added 3 quarts and took it for a drive.  It said to add 2 quarts, which seemed high so I added one quart, drove it and checked and it said OL OK. 

[FLynes]

12 hours ago, Ivan K said:

Ha, yeah, ATF expands with temp significantly so it has to be meassured hot. I think 160F was the minimum for the system to even start. I suppose at you normal cruising temp would be the time to do it.

A quick look into the library says this: 

To ensure an accurate check, operate the transmission until the sump fluid

temperature is 160–200°F (71–93°C); converter-out temperature is

180–220°F (82–104°C).

If anyone on the forum is not a member of the Allison Hub, joining is free, and it gives you access to all of the digital files for our transmissions. Here is the link to access the site: https://hub.allisontransmission.com/login Once you're a member, you can navigate to https://hub.allisontransmission.com/my-transmission and enter your transmission's serial number, which will give you access to everything Allison has to offer for your model transmission.

I'm attaching a few files for your perusal.

Allison Motorhome Series.pdf Allison Transmission Fluid and Filter Change Recommendations Rev. Y.pdf Allison Oil Analysis Test Recommendations.pdf

Edited October 14, 2023 by FLynes

[dl_racing427]

1 hour ago, FLynes said:

If anyone on the forum is not a member of the Allison Hub, joining is free, and it gives you access to all of the digital files for our transmissions. Here is the link to access the site: https://hub.allisontransmission.com/login Once you're a member, you can navigate to https://hub.allisontransmission.com/my-transmission and enter your transmission's serial number, which will give you access to everything Allison has to offer for your model transmission.

I'm attaching a few files for your perusal.

Allison Motorhome Series.pdf 3.3 MB · 1 download Allison Transmission Fluid and Filter Change Recommendations Rev. Y.pdf 1.13 MB · 0 downloads Allison Oil Analysis Test Recommendations.pdf 986.17 kB · 1 download

Thanks for this info.  I'm sure it will prove invaluable to many Monaco owners.

[Ivan K]

Someone doing a first fluid change should not blindly follow their database to find the right filters. Back when I did, Allison indicated a shallow pan for my SN. Did not sound right so I measured it and have a deep pan = longer filters. 

[96 EVO]

13 minutes ago, Ivan K said:

Someone doing a first fluid change should not blindly follow their database to find the right filters. Back when I did, Allison indicated a shallow pan for my SN. Did not sound right so I measured it and have a deep pan = longer filters. 

Yep!

I have a brand new set of 'short' filters staring me in the face when I step in my garage, just to remind me to CONFIRM, before ordering parts 🤬!!

[FLynes]

5 hours ago, Ivan K said:

Someone doing a first fluid change should not blindly follow their database to find the right filters. Back when I did, Allison indicated a shallow pan for my SN. Did not sound right so I measured it and have a deep pan = longer filters. 

Is it possible the previous owner replaced with a deeper pan? I ask because I did that with my ‘05 Dodge Ram, right after I bought it new.

[Ivan K]

55 minutes ago, FLynes said:

Is it possible the previous owner replaced with a deeper pan? I ask because I did that with my ‘05 Dodge Ram, right after I bought it new.

Certainly a possibility, it would be the only thing different from what was factory equipment. Either way, if I did not see the pan before ordering I would have bought wrong parts.