Transfer Case Temperature

[afgunn]

Just changed the fluid in the Transfer Case in sig below and went for a drive of about 50 min. - 50% at ~60mph and the rest stop and go at 45mph. The transfer case was hot - just a little too hot to keep your hand on it but not as hot as the auto trans pan. Is this about right? I thought the Transfer Case would be cooler since it is was in 2H and not actually being driven (as in 4L or 4H) - although it is a live axle!? Did another drive on the Interstate for ~ 1 hour. Transfer case was too hot to keep hand on and was hotter that the trans pan!Is any of this normal? I do REALLY want to know!?

[Mopar1973Man]

What kind of fluid did you use? When you changed it did you get any debris or metal out of it? Heat seem to be a bit hot side really... I wonder if the bearing problem? Also on the later trucks 2001.5 and up the front shaft is always turning too... It disconnected but still turning with the front wheels...

[afgunn]

I used the ATF-4 fluid that is recommended. I did not look at the fluid close because I was so distracted - cleaning up an unexpected mess! It did look somewhat dark though. Do not know if there were any shiny particles though - no large chunks for sure. The rear bearing in the tail housing was replaced since I was putting on a different setup.I plan on changing the fluid again this fall in order to get a good flush.It was my thought as well that it is not driven but it is turning. I expected it to be only mildly warm. Also, someone mentioned that heat from the trans could be transfering into the transfer case since they are mechanically connected. I did not check the temperature of the trans case - just the pan.Next time I think I will check the temp with a temp probe. I was just hoping someone had some first hand experience. I wish I did! Wish I had checked these temps before I did any work - just had no idea!

[Mopar1973Man]

Next time I'm out and about i'll check mine out and see how mine is compare...

[afgunn]

Thanks! Exactly what I need!

[afgunn]

Again, went for a drive of about 50 min. - 50% at 60mph and the rest stop and go at 45mph. Checked the temperature of the Transfer Case and it was 130*F which is well below the 175*F point at which ATF-4 starts to break down. So, I think I am OK. Just surprised it gets that hot but some heat may be coming from the trans.

[Wild and Free]

Again, went for a drive of about 50 min. - 50% at 60mph and the rest stop and go at 45mph. Checked the temperature of the Transfer Case and it was 130*F which is well below the 175*F point at which ATF-4 starts to break down. So, I think I am OK. Just surprised it gets that hot but some heat may be coming from the trans.

Where did you get the info of ATF-4 breaking down at 175*? It is a partial synthetic and I have never seen an oil that degrades at that low of temp. Even with carbon based oils you are good to 200ish most synthetics will take a lot higher temp for a lot longer before breaking down. Rule of thumb is anything over 210-215 for extended periods is bad anything under 200 is ok for extended periods.

[afgunn]

Thanks for your reply and the info! I should have said "shortened life" or "drain interval". I read that the replacement interveral is shorteded when the oil gets above 175*F but it is not shortened by much at 200*F. And... I was not thinking of synthetic or partial synthetics. I got the chart here: http://www.txchange.com/heatchrt.htm

[afgunn]

Took a 3 hour drive Saturday (mostly at 70 mph) and checked the temps.Transmission pan - 115*FTransfer Case - 138*FBoth are well below the 200*F point where the change interval starts to get shortened.

[Mopar1973Man]

Yeah... I checked mine its warm to the touch but not really bad...

[Wild and Free]

You need to remember that it only holds 3.5 quarts of oil and has no cooling other than air flow and it takes all the power transfered from the engine unlike the tranny which holds around 4 gallons and has 2 seperate coolers.

[Mopar1973Man]

Or like a manual 5/6 speed trans gets reather warm too because of the same reason... No coolers, etc...