Ford Transfer Case Large.

Tim Berry · #1 17-10-06, 00:15

Hi all. I recently attended the MJCQ swap meet at Canungra Qld. It was a round trip of about 450km's and ten hours on the road. On the way home on the Sunday the ambient outside temp was 35 celcius and you could not touch the road surface. I believe these conditions may have helped my rear left tyre to blow out. It appears to have been a complete side wall failure.
My questions is though, how hot should the transfer case get. After an hour of travelling and changing the tyre, I decided to check the oil level in the case. I could not touch the housing or the filler plug it was that hot. It had plenty of gear oil in it. Is this normal. I am running 80/90 gear hypoid oil. Is it also true these transfer cases only run on two and a half pints of oil, as I think I overfilled mine causing it to leak badly out of the seals.
For those in Australia, where can I get the steel shims from to set bearing pre loads. My transfer case internally was in good order so we cleaned her out and put it all back together as found. One thing I noticed was the lack of shims in general. There may be one of two at most but that is all. Is that normal. I was think bearing preload may be too high causing the high temps but I am no engineer. As I said we assembled her again as found. Any ideas?

Tim

Tony Smith · #2 17-10-06, 03:36

When you say "Transfer case large", have you got a 2-speed case in your F15A? The single speed case originally fitted should, according to the Aust Army handbook, have 2 pints (1.2lt) of 90 grade hypoid oil, while the large 2 speed cases should have between 3 pints (1.8lt) and 3 1/2 pints (2.1lts), depending if a PTO is fitted or not. The manual says 90 grade is normally used "in temperate climates". The fins cast in the sides of the case aren't just for strengthening, they also cool the case.
As for sourcing the shims, have you tried Ross Prince?

Lynn Eades · #3 17-10-06, 06:32

I don't know about the CMP cases but it was considered normal for the 6x6 Dodge transfer cases to run pretty hot...Too hot to put your hand on.

Rob Beale · #4 17-10-06, 07:25

it specifies SAE 140 for summer and SAE 90 for winter.

I know that my C8AX's transfer case gets hot on long trips. I have run 85 / 140 grade for 15 years now in all seasons. (I use it in the diffs too, and straight SAE 90 in the gearbox.)

Rob

jim sewell · #5 17-10-06, 10:53

Gearbox's and diff's will appear hot to touch and this is quite normal , usually we do not have the need to feel the temp , speed and load will increase the friction hence the heat .
A friction modifier can be used if you are concerned .
The general rule is not to discolour the paint .
Regards
Jim S.

Tim Berry · #6 18-10-06, 00:28

Yes I have the two speed case under my F15a to give me high and low range. I drained the 90 weight oil and it is a dark caramel colour. Not metal evident in the oil. The paint on the outside of the box is still the normal colour with no blistering off. I was running at 40 mph on the 900x16 tyres for most of the way. The box is not overly whiny or growling, just the normal straight cut gear noise. I was asking about the heat to guage if my bearing preloads may be too high without having to disturb too much of the transfer case yet. If others are running hot then I will be happy. By too hot to touch I mean bloody hot. I tried Ross Prince for shims a while ago and he had none at hand.

Tim