Community Forums

Hardlyable · 10-20-2015, 08:52 AM

I have 2014 Duramax, Chev 3500 HD, Allison 1000 series, 6spd. Notice even on hardpulls, +85F outside air temp, 16,000 lb. Raptor 5th wheel, 2-5000 ft elev, transmission temp rarely exceeds 153F. In older Chev xmissions (4L80e) ran 220, 230F or more. Always understood 160F was a minimum temp to shoot for. Is this normal for these 1000 series xmissions to run this cold? Had a 5spd Allison in a Chev 2002 with 8.1 liter gas, and it would run around 200F. Anybody have any experiences or maybe "MrTranSynd" may have some info... Thanks for your help..Kent

NevadaNick · 10-20-2015, 04:54 PM

I had a 2011 GMC crewcab dually and the temps were always low like that. Cant remember it ever going over about 170.

NevadaNick · 10-21-2015, 08:24 AM

For the record, my 2500 series in my motorhome which is nearly the same as the 1000 runs around 180 and up to 203

TimLoon · 10-21-2015, 05:47 PM

My Allison 1000 in my w20 chassis has never exceeded 170 degrees. Run a partial blend of Transynd.

dfm · 10-21-2015, 06:19 PM

The OEM thermostats are usually 180 and 185 degrees. You can get 185 and 190 degrees thermostats if You are operating your vehicle in a cold climate. If you are only getting to 150 or 160 degrees You likely have a defective thermostat and should replace them.
A hotter temperature will give you better fuel economy as well.
I know because I just change mine on Saturday for the same problem. If you can use a socket and a screwdriver , It's not too difficult as a Diy project.

TimLoon · 10-22-2015, 04:06 AM

I thought we were talking about transmission fluid temps and not engine temps. Somewhat related but two different matters. BTW, my tranny temps are read through my ScanGaugeII.

Civdiv99 · 10-26-2015, 08:26 PM

My trans runs about 160 or so cruise. Maybe up to 180 on longer climbs. Likewise this is via Scangauge II.

coopcolt · 01-14-2016, 05:28 PM

Seams to me somewhere along the way, when I purchased the Scan-Gauge
I remember that you need to add 20 degrees to the temp that the
S/G reads. Something to the affect that the pick-up was NOT in the hottest
area of the tranny. In my 02, W-20 my S/G reads like 150/160+.
So for yrs. I have just added 20 and we have both been happy......coop

1ciderdog · 01-14-2016, 05:40 PM

A transmission guy once told me most automatic transmissions will run 80 to 100 degrees above outside air temperature. Seems kind of true for my RV. I don't think you need to worry about transmission temps unless they consistently read above 200 (Just my opinion)