Changing Planer Gear Oil?

[Mark W Pugh]

OK, so I have this old Buffalo 15" planer and I'm sure the gear oil has not been changed in YEARS, if ever. What kind of oil are we talking about? Does it really ever need to be changed? Nothing in the owners manual on type of oil. The manual just says to change it. Thanks.

[glenn bradley]

My 15" uses 90 weight gear oil.

[Chris Parks]

Why bother? The reason we change oil is either from metal or fuel contamination neither of which should be an issue on a planer which has a relatively slow chain or gear drive.

[shane lyall]

My North State 20 inch (same machine as Powermatic, Jet, Griz) uses 90w. Not a bad idea to change it every now and again. Mine has brass bushings and there were some powder like fines in it when I changed it. It had been running for a few years so not much wear. It may run forever on old oil but I tend to er on the side of caution in such matters.

[Steve Meliza]

Oil can be purified and reused with special equipment, but eventually acids tend to build up and the oil will need replaced. The systems and purifiers I worked on in the past tended to lose oil over time due to leaks and maintenance so it never had to be changed, just topped off (purification was a 24/7 operation). New metal parts have sharp edges and rough surfaces that wear a lot in the first several hours of operation so all oils should be changed once early in the life of the tool and periodically throughout to flush out metal wear particles.

[Rick Pettit]

My manual states 50w gear oil. I bought some transmission oil from the local hot rod shop. I've read on owwm of some other sources.

[Van Huskey]

When you drain it I think you will see that you probably made a good choice to replace it, it will be nasty.

I am reluctant to recommend an oil but any multi-purpose gear oil will be fine, I would probably get 90w but lower viscosity would be fine as well.

[Mark W Pugh]

Thanks for all the replies. There is no "how much", so how do I know when enough is enough?

[shane lyall]

There should be a fill plag on the side of the case. Add oil until it is up to the bottom of the fill hole and cap it off. Done

[Chris Parks]

Oil can be purified and reused with special equipment, but eventually acids tend to build up and the oil will need replaced.

It is not an IC engine it is a primitive gear train or chain drive, nothing more or less. It could operate dry for quite a long time if needed, they are that slow.

[Michael Mayo]

I would not recommend running it dry as stated. I just did my DC 380 that was new to me and used some heavy weight gear oil I had left over from my truck differential replacement. I think it was 140 weight or something like that. It was very viscous like molasses and that is what came out of the machine when I drained it. Be advised that if you overfill the gearbox you will likely end up with some leaking. Don't ask me how i know this.....;) I would just fill it till some oil starts to drizzle out of the fill hole then allow it to drip until it stops and you should be good to go for many more years to come.

[Steve Meliza]

Yah, don't run dry and don't over-fill as that could lead to foaming and air bubbles don't cool or lubricate very well.

[Chris Parks]

Yah, don't run dry and don't over-fill as that could lead to foaming and air bubbles don't cool or lubricate very well.
It won't turn fast enough to foam anything.

[Van Huskey]

It won't turn fast enough to foam anything.

I agree with this, nothing to cause air entrainment and even with moderate aeration nothing really to be harmed by it, no pump to cavitate and no hydraulics to have issues with.

I do however think changing the oil is cheap insurance and I can say that oil that has been inside a planer for any length of time is pretty nasty.

[Steve Meliza]

The only other mention I can find of a Buffalo 15" planer is here on SMC and the guy is looking for parts because he thinks a drive gear is going bad. The only suggestion he gets is to call Grizzly to see if any of their parts will fit.

Mark has 4 choices based on the suggestions received:
1) Run with the oil that is in there as long as possible, hoping for the best.
2) Drain the oil and run dry, ensuring prompt destruction.
3) Drain the oil a refill to the bottom of the plug hole, giving the gear box the best chance of survival to old age.
4) Drain the oil then overfill because maybe it won't matter. After all, if a little oil is good a whole lot is better.

I really hope the suggestion to run dry is a joke or an illustration in trying to make a point. Similarly, I do hope the reasons why others think that over-filling won't cause harm is speculation rather than a suggested maintenance practice. If the box does in fact as gears as mentioned in the other post then clean oil to the fill mark will result in the longest life of the gears with minimal lash. But what you're also protecting are the bearings, and I don't care how slow the shaft is turning, a loaded bearing needs cooled and lubricated.

[Van Huskey]

Similarly, I do hope the reasons why others think that over-filling won't cause harm is speculation rather than a suggested maintenance practice. If the box does in fact as gears as mentioned in the other post then clean oil to the fill mark will result in the longest life of the gears with minimal lash. But what you're also protecting are the bearings, and I don't care how slow the shaft is turning, a loaded bearing needs cooled and lubricated.

If it is like most planers I have seen you can't really overfill it since you fill up to the fill plug, any attempt to add more oil would simply cause the excess to run out as you filled it. Are the bearings in a 4 post planer's gearbox open, I don't ever remember seeing anything I didn't think was sealed bearings, I thought the oil was just for the chains and gears.

[Correy Smith]

I just put in a Shelix in a Delta 15". I too am trying to source EP Gear Oil. 50w. Delta has it listed in their parts break down as a 20oz. bottle. I drained about 16 oz. of 7~8 year old oil that had a slow sela leak. So may have been 20 oz once upon a time. I am unsure if we are taliking of the same "gears". I believe the helical gear on the end of the cutter head is moving quite fast, isn't the head spinning 3500 or faster? The gear is only about 1" dia. Sure, the feed speed gears are larger moving slower. But it was recommended Extreme Pressure oil. And was told high RPM's will require this. Hard to source....

[Correy Smith]

What type oil is used in the 15" Planer gear box?Delta says this for it's 15" planer......The machine was originally filled with approximately 20 ounces of 140 weight, EP (extreme pressure), gear oil.
If adding oil, use 140 wt. EP gear oil.
If changing oil, either 140 wt. EP gear oil, or 85W140 wt, multi-viscosity EP gear oil may be used. Fill to the filler hole.
The 85W140 with EP Additive is available as Delta service part number 999010131210.
DO NOT MIX oils of different types or viscosities.