Teking, I'm finishing up the rebuild of my LU-4 Braden winch. Learned a few things in the process. You might download the generic "Braden Worm Gear Winch" service manual. Copy and paste:

http://www.paccarwinch.com/pdf/pb-162.pdf

This is a general manual that covers Braden's many worm gear winches. Paccar Inc is the parent company that absorbed Braden, Carco and Gearmatic winch companies along with names like Kenworth and Peterbuilt. From the company history on their web sight:
In 1955 Braden Winch Company designed and manufactured the Model LU4, a 7,500 pound water tight winch for military vehicles.

Thanks Brut4c! You did a great job with the online manuals. See that winch info here:

http://www.m715zone.com/manuals/34/c...0section2.html

Like Spicergear said, moisture gets into the worm gear housing over time and corrodes and pits the steel worm gear and tapered roller bearings. The oil covers only the lower half of the worm gear and bearings, so its best to operate the winch periodically to lube those parts above the oil that are exposed to the moist air. Draining, flushing and refilling the gear oil should help remove any water that has been sitting in the bottom of the cases For flushing, Braden recommends draining and refilling with kerosene and running for 5 minutes with no load and then draining and refilling with the correct gear oil. In their manual, Braden states that it is normal to see a small amount of fine bronze particles in the drain oil; however large flakes or chips requires winch disassembly for inspection.

Kaiserjeeps is also right on with the oil info. I know that the M715 Lube Order calls for 90wt gear oil but the manufacturer calls for 140 wt gear oil (AGMA Grade 7EP) for ambient temperatures above 40 degree F. Between 10 F and 50 F it calls out 90 wt. There are other grades of oils listed for lower temps. I ended up using an 85w-140 wt gear oil that should cover most conditions I encounter. One quart is all you will need. After draining out the old oil, put a little over half (18 ounces) into the worm gear housing and the rest (14oz) into the clutch housing. There are two small 1/8 inch pipe plugs, one in each housing, that you can remove to check the oil level. I never knew they existed until removing the winch and cleaning off the housings.

The worm shaft brake assembly seems to be a source of problems. Mine had a mixture of water, oil and rust inside. The front worm shaft seal had leaked oil and the previous mechanic had installed the cover with the brake band holes facing up, thus catching rain water. By design, the brake housing does not get a gasket, so it should be installed with the brake band holes at the lower point which will help drain out water Guys, the brake band can also be installed backwards. The Braden service manual has a good picture of the correct installation on page 32. It’s allows the worm shaft to turn freely for winching “in” but provides worm shaft braking if winching “out“. Normally you would disengage the winch clutch to spool out the cable, not power the winch out.

The design of the worm gears provide the majority of winch holding ability. The gear ratio is about 29 to 1.

On a safety related note, I also learned that the clutch lugs (dogs) have a “negative draft angle” cut into their faces to prevent disengagement under load. Instead of the faces of the lugs being cut at 90 degrees, they are undercut slightly to load the sliding clutch in towards the drum during winching. The manual explains how to check this “negative draft angle” without disassembling the winch. This is good info to read on page 10 to tell if the dogs are worn out. Mine were shot requiring a sliding clutch replacement and reworking the clutch dogs on the cable drum. This damage is caused by attempting to engage the drum clutch while the winch is running or disengaging the clutch with a load applied to the winch cable.

Most of the original seals had a felt wiper built in to them. Since these are no longer available, make sure that the replacement seals are “double lipped” to help keep out water and crud.

I got my winch parts from AB Linn and Vintage Power Wagons

AB Linn’s email (no web site): ablinn@salisbury.net

Vintage Power Wagons web site:
http://www.vintagepowerwagons.com/pr...nch/lu4-p1.htm

Hope this info is helpful, Robert-CA (aka Hiker)