lC 80 transfer case running hot

[Too Tall Ted]

Installed part time kit on my 97 with new bearings on the center idler cluster and some low gears. TC seems to be running hot. It is definitely hotter than the auto trans after only 10 miles. I can barely put my hand on it after a drive. How bout yours? Jump under. And give yours the feel test and post your report here!! I suspect the preload is too tight on the center gear cluster.

Thanks in advance y'all.

 

[Tapage]

measure yours with a laser temp gun after a X miles flat trip .. that will make some " measurable " parameter to compare with ..

 

[scottryana]

Yeah I notice mine runs hot as well but I think that is kind of the nature of the beast. All the power runs through the TC and yet it has less than 2L of oil in it. While the transmission has 10+ and the diffs have 5+ combined. If there is any place on an 80 that should get the highest quality synthetic oil I believe it's the transfer case.

 

[Kernal]

I've measured the temp of my transfer case with an IR thermometer in the past. After 30-45 minutes driving 45-55mph I get ~130-140'F depending on ambient air temp (40-95'F) using synthetic gear oil.

 

[Howard705]

Yeah I notice mine runs hot as well but I think that is kind of the nature of the beast. All the power runs through the TC and yet it has less than 2L of oil in it. While the transmission has 10+ and the diffs have 5+ combined. If there is any place on an 80 that should get the highest quality synthetic oil I believe it's the transfer case.

I've never paid any attention BUT the transfer is all straight gear (unless stuck spinning visc coupler)-the oil lubes only. the A/T has lots of hydraulic going on/high pressure pumping-holding clutch packs-lockup-converter slip-all through valve body etc-BTW this heat is one of the reasons A/Ts aren't always at max pressure unless as needed to hold for hard loads

 

[rc51kid]

not to hijack. But what weight and type of synthetic oil do you recomend for the t case?

 

[scottryana]

I use Mobil 1 75-90 synthetic, easy to find good quality.

 

[Howard705]

Installed part time kit on my 97 with new bearings on the center idler cluster and some low gears. TC seems to be running hot. It is definitely hotter than the auto trans after only 10 miles. I can barely put my hand on it after a drive. How bout yours? Jump under. And give yours the feel test and post your report here!! I suspect the preload is too tight on the center gear cluster.

Thanks in advance y'all.

would think enough preload to make that big case that hos would be damaging the bearing. When I've seen rear axles get very hot they didn't last long.

 

[Too Tall Ted]

Thanks for the thoughts everyone. The fluid was cloudy and with the heat I decided to pull the case and re-check everything. I replaced the rear bearing on the center idler cluster (thanks C Dan). I backed out a bit of pre-load on the bearings. Putting it back in today and we'll see.