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Topic: TRANS TEMP. (Read 551 times) previous topic - next topic

TRANS TEMP.

I have noticed that when I warm up the coach (bringing it to operating temp both engine and trans) the trans. temp. rises quickly( to about 275) if I shift into drive and reverse while holding the brake ( 1 min. or more in each position). The temp drops quickly when back in neutral.
Is this normal?
1995 U320C SE 40'
Jeep 4x4 Commander - Limited - Hemi
"The Pack"  Yogi and Diesel our Airedales -  Charlie our Boxer/Akita mix. Gone but NEVER forgotten Jake our yellow Lab.
NRA Law Enforcement Firearms instructor - Handgun/shotgun
Regional Firearms instructor for national Armored Transp. Co.

Re: TRANS TEMP.

Reply #1 –
No
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: TRANS TEMP.

Reply #2 –
My trans temp warms up very slowly at idle. When driving it stays around 190
1995 U320 40', 2013 chevy sonic toad, my real love are corvettes have owned 30

Re: TRANS TEMP.

Reply #3 –
It is either your intake manifold sensor or your water temp sensor. If it is cold my intake air temp will go up helping warm up the engine but the engine and transmission warm up slowly.  I never see the tranny above 140 even when I am driving starting out. It hovered about 170 in normal driving then would run a couple degrees cooler then the engine. Never saw those higher temps unless I was losing a sensor.
2025 Wanderbox Outpost 32 on F600 Expedition Motorhome
2015 Born Free Royal Splendor on Ford 550 nonslide version  for sale
Former Coaches  covering. 360,000 miles
1999 34 U270
2000 36 U320
2001 42' double slide U320
2018 Jeep Rubicon

Re: TRANS TEMP.

Reply #4 –
If the transmission is in a gear that is in "lock up," there is no slippage and the transmission temp will be cooler. City driving will frequently see higher trans temps as the torque converter is "slipping" and making heat in the lower gears. Highway driving in coaches with the lock up feature in their Allisons will usually run about the same temperature as the engine.

Earlier Foretravels may not have lockup and run higher tranny temps. The transmission heat exchanger is designed to lower the transmission fluid temp. The higher the transmission temperature (over an extended period), the shorter the transmission life. Lock up will also be more fuel efficient as less energy is spent making heat.

I back up my driveway as the 4.xx to 1 ratio in first gear rapidly heats the fluid to over 300 degrees in the first 300 feet. Backing at 6.xx to 1 keeps slippage to a minimum and does not heat the trans over what the heat exchanger can control.

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

Re: TRANS TEMP.

Reply #5 –
If you have never seen Pierce's driveway you will probably not understand what a feat this is !!!

My little Mazda pickup had a difficult time going up. BUT THE RIDE DOWN WAS FUN !
1993 U300, 6v92
build 4366
USAF retired, Flight Engineer, C124, C130
 ATP, A & E.  & ex AI

Re: TRANS TEMP.

Reply #6 –
Lon,
Check your idle speed.
If just a little high it will raise transmission temp when sitting still in gear.
Sitting in traffic it will go up. I put it in neutral between light cycles when sitting in heavy traffic but it shouldn't go up that fast.
John Duld
1995 U320C SE 40'
 

Re: TRANS TEMP.

Reply #7 –
Quote from: John Duld –

Sitting in traffic it will go up. I put it in neutral between light cycles when sitting on heavy traffic but it shouldn't go up that fast.

I do exactly the same thing.
Brett Wolfe
EX: 1993 U240
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