How cool is too cool?

[RV'nOldTimer]

Transmission is the five speed 2500 in a 2006 Winny Journey 32T.

I am aware of the danger of running any tranny too hot, but mine, if anything seems mighty cool! It routinely runs from 120* F to 150* F, reaching 180* F, tops, after a hard mountain climb. Is this a problem or should I be happy? This is the data from the Silverleaf VMSpc. Thanks for any insight.

JT

[Pusherman]

Don't worry. Be Happy.

Allison transmissions need to be about 140-150F to be 'warm' to check fluid levels, etc.

Synthetic oil does run cooler than Dino.

[Dave1956]

I do not know what the actual temps were, but on my last trip from Houston to OK City, outside temps were about 35-40 and the tranny temp never came off the botton of the gauge.

On the return trip with slightly warner air temps the tranny came up to the first indicator line on the gauge.

I have a 300 Cummins freightliner.

[DAN L]

Quote:

Originally Posted by RV'nOldTimer Transmission is the five speed 2500 in a 2006 Winny Journey 32T. I am aware of the danger of running any tranny too hot, but mine, if anything seems mighty cool! It routinely runs from 120* F to 150* F, reaching 180* F, tops, after a hard mountain climb. Is this a problem or should I be happy? This is the data from the Silverleaf VMSpc. Thanks for any insight. JT

jt,
imo your temperatures are normal.
I use a scan gauge 2 to monitor my 5 speed ally temperature. my normal fluid temperature is between 137 and about 170 degrees. i use amsoil synthetic tes295 fluid.
descending the east side of mt charleston, nv. mostly in 1st gear, my ally temp climbed to over 200 degrees. this is a steep descent from 7500 ft. to less than 1000 ft. altitude in about 15 miles. i stopped once about 2/3 of the way down to let the engine idle for about 10 minutes to cool the tranny. we were towing a nissan altima on a dolly. next time we go down that mountain, my dw will drive the toad.
mt charleston has several beautiful national forest campgrounds. one has 50 amp electric and water for $15.50 a day, 2 weeks maximum stay. this cg is near the mt charleston resort which has very good food and free wifi internet access.

[RV'nOldTimer]

Thanks guys.

I have assumed that the cool readings were OK but wondered what others thought. I have noticed that on a cold start that the Allison doesn't shift into top gear until the temp rises a bit but I've not gotten a reading on just where this occurs. I've only had the VMSpc for a short time so there has been no opportunity to pick up on some details. The Allison 2500 requires an approprate synthetic fluid but change interval is 100K miles.

Good travels.

JT

[Steve Ownby]

JT,

Check the change interval. There is also a month limit which is the one that usually is the reason for changing the fluid & filter in motorhomes.

Don't let it go too long.

Safe travels,

[David K]

I would agree with Steve's comment re a time limit causing a fluid change before the mileage. On my 3000, the mileage is 75,000 miles but a 3 year interval when running synthetic fluid. The time limit will get me before the mileage.

[RV'nOldTimer]

Quote:

Originally Posted by David K I would agree with Steve's comment re a time limit causing a fluid change before the mileage. On my 3000, the mileage is 75,000 miles but a 3 year interval when running synthetic fluid. The time limit will get me before the mileage.

Yep, agreed that many/most lub changes on MHs are time driven rather than mileage. Don't have the manual here now but I seem to remember the my Allison 2500MH with Transyn has a five year cycle. The one that seems uncharacteristically often is Freightliner's yearly change of differential oil. No other vehicle that I've owned specifies that frequent a change for a gear box.

JT

[DriVer]

Quote:

Originally Posted by RV'nOldTimer The one that seems uncharacteristically often is Freightliner's yearly change of differential oil. No other vehicle that I've owned specifies that frequent a change for a gear box.

JT, We broached that subject last week during the Freighliner Chat session and that question was asked and answered. Company rep, "FCCC Service" said that the differential fluid should be changed every 24,000 miles or 2 years WCF using 80-90W conventional mineral based gear oil.

The NEXT FCCC Chat will be held on Tuesday February 1st, 2011 at 9:00pm EST.

For more information call: 800 FTL HELP.

[RV'nOldTimer]

Quote:

Originally Posted by DriVer JT, We broached that subject last week during the Freighliner Chat session and that question was asked and answered. Company rep, "FCCC Service" said that the differential fluid should be changed every 24,000 miles or 2 years WCF using 80-90W conventional mineral based gear oil. The NEXT FCCC Chat will be held on Tuesday February 1st, 2011 at 9:00pm EST. For more information call: 800 FTL HELP.

Thanks DriVer,

That sounds much more reasonable and uses half to oil

JT