VCCA Home
Posted By: TIFFIN28 1928 Transmission and rear end oil change - 01/28/12 10:01 PM
Hey guys, Just ordered some 600 wt from the filling station. What is the best way to drain and flush out the old oil from the transmission/rear end drive line?? Car is in storage till spring, but i would like to get started with the oil change. Hope 4qts will be good enough. Thanks for the ideas as always...John



Ideally, you should drive the car and warm up the transmission and rear end. Otherwise the heavy oil will take a while to drain. I really don't see the necessity to flush either one. When warm remove the plugs (a bottom bolt on the rear end) and let drain for perhaps several hours. Refill with the 600 you purchased and you will be "good to go".


devil Agrin
Ray,
I would add checking for metal particles in the drained fluid before refilling. Passing a magnet across the bottom of the container (if it is not magnetic) is less messy.
Many years ago,I got a small round magnet and used high strength epoxy to retain it in the original drain plug on the 4spd gearbox in my truck.
About every 2 years I let the gearbox drain o/night,re-fit the drain plug,fill with kerosene or diesel,then re-drain and refill with gearbox oil.
It's surprising just how many metal particles are on the magnet at the first drain,and how many more there are at the second drain.
devil
Thanks for all the info, Thought I might use a halogen light to warm the case up (and oil) then drain?? Book said something about flushing out with light engine oil also adding pint of engine oil for winter (better shifting?)your thoughts on this for summer? Or better just use straight 600 Thanks.....John
Seeing you're laid up for a while, I'd suggest you drain the diff as Ray suggested. take the cover off and clean out all the residue in the bottom of the housing. When I did this in my 34 Master I found pieces of bronze from a collapsed cage, a magnet will not find this.
Check the coverplate for warping as due overtighening of bolts this tends to happen. Staighten it out as best you can. I use a 3mm thich neoprene cork gasket as it has more 'give' and I use a good quality wet gasket cement which helps.
Down here in Aus. we use 140 SAE which is basically the same as 600W.
Chris
HI, I've got a 1928 Chevy National. picked up the same 600w from filling station.

I've located the cap and plug, might take the top cover off if I can find some of the aforementioned cork gasket but I am very curious as to how much I should put in, as it was never mentioned in this thread. I have 10qts as I plan to do rear diffs and trans for both of my '28s

any help would be appreciated
I would suggest purchasing an owners manual from the Filling Station for $15. It will also show the parts that require lubrication that you are not aware of.
I agree that you need an owner’s manual and a shop manual. Typically the transmission will take about 1 1/2 guards and the differential about 1 quart.

You fill them until fluid is just ready to run out of the fill plug hole. The vehicle must be sitting level when you fill them.
Don't forget the u-joint cavity. It also uses 600W oil.

I keep some 600W in a squirt oil can so I can squirt it into the 1/8 NPT hole in the u-joint housing.

To make sure I have enough oil in there, I made a little dip stick out of the strip of steel that was in an old windshield wiper blade. See the attached pic.

I happy with between 3/4" and 1" of oil showing on the dip stick. Any more than that seems to leak out of the ball housing end.

Cheers, Dean


Description: Homemade u-joint housing dip stick.
Attached picture u-joint-dip-stick.jpg
I just did this in my '25 and 4 1/2 - 5 quarts is all you will need. I filled the transmission, U-joint bell and the rearend and probably used a little less than 4 1/2 quarts
© Vintage Chevrolet Club - Discussion Forum