600 W oil / STP

Bobster

Member
I am doing some work on the rear axle on my 1928 Roadster. I was going to fill the banjo with 600 W oil, but a fellow restorer claims that STP added to the mix will be beneficial. STP is thick and may not circulate about as well as the 600 W equivalent. I have one source that claims the "modern" 600 W is nothing more than 140 W gear lube. What is the best way to go here. I don't want to "gum" up the works. Thanks, BW
 
Bobster - IMHO, I don't feel you need to add STP to the 600w oil. Others have, and they believe there are benefits. My experience using only 600w has been ok in my transmission and differential.

You may already know this, but 600w oil is not 600-weight oil. In terms of consistency, 600w oil is similar to the consistency of 140-weight gear oil (just my perception, others may differ). Others still have used 140-weight gear oil from the parts stores, and have gotten along fine.

STP is marketed as an additive for (again IMHO) over-coming oil consumption in engines. I would stick with the manufacturers suggestion.

I guess my short answer would be you will not have lubrication problems using the 600w oil sold by the Model A parts vendors.
 
From all the STUFF that I have read, 600W is anywhere from 160-250 weight.. I happen to be happy with plain ole 140 weight.. Back when Studebaker owned STP we had to try and sell that crap to everyone that walked thru the door.. I think you can tell from that statement what I think of the product,, but,, it does make for a nice assembly lube..
 
Several years ago we had the 600W tested by a chemist. They reported you could get the same benefits by using 140 W and STP using 75% 140W and 25% STP. SInce then we found another product called Lubriplate SPO288 which is made for lubricating straight cut gears. See the Model A Times Vol 1 Issue 1 and Vol 5 Issue 1.
 
Lubriplate SPO 288 and SPO 299 are specifically engineered for spur-gear and worm gear drives, and are modern equivalents for 600 weight heavy gear oil.

600W seems to be a little confusing - some reference sources define it as "steam cylinder oil", which is a heavy, clinging oil designed to be used in the presence of water. From the data I have read from modern refiners / suppliers, the modern equivalents for 600 gear oil are NOT good for applications which will expose the lube to water/moisture.

Steam cylinder is still available too.

One of the chief "safe qualities" of 600 weight heavy gear oil is that it is safe for use with "yellow metals" ( bronze / brass / copper ). Most modern gear lubes contain sulfur compounds, which attack and corrode yellow metals.
 
If you buy the stuff from the Model A vendors, 99% of them use 160-240 weight oil with STP already added.

Those that don't advertise the fact that is it "true"" Mobil 600W.

Wher did you get yours and what did the bottle say?
 
Snyder's and Bratton's advertise the 600 W oil. Don't doubt their claims for authenticity / duplication of original lubricants. STP was touted to add life to your worn engine back in the 70's. It effectively stopped up the flow of oil in my 1988 Oldsmobile and caused some overhead valve problems - rocker arms went dry. I have had some apprehensions about STP since then. Model A motor / drive train might forgive or need heavier lubricant. BW
 
Re: 600 W oil / STP / inner axel seal

I have ordered inner axle seals from 2 providers. Neither of the suppliers shipped a seal with a supporting spring backing the rubber . The originals have a spring. Since these seals keep the oil out of the hub bearing, I am thinking they should be more substantially made. Have I latched on to a cheap after market part? Are better / heavier seals offered? Don't want to do this again in near future. Thanks, BW
 
Bob, I would think your post would get more attention if it were posted to a new thread in the general Model A forum. This thread is about 600w oil and STP...not inner seals.

Just MHO...
 
From all the STUFF that I have read, 600W is anywhere from 160-250 weight.. I happen to be happy with plain ole 140 weight.. Back when Studebaker owned STP we had to try and sell that crap to everyone that walked thru the door.. I think you can tell from that statement what I think of the product,, but,, it does make for a nice assembly lube..

Aside from Assembly, which it is good for, What's wrong with STP? I've read somewhere it had a "sticky" quality that oil doesn't have. Also, I had a friend who said that engines that were lubed with STP would run longer with out oil than those on straight oil. (Not much longer, but longer) I admit, I never tested it out. But I used STP as an additive for years with
no ill effects. However. It doesn't work in Ford/Mazda 5 speed transmissions. If you have one, DON'T put STP in it. In the case of engines, did I waste my money adding it for all those years?
Terry
 
Lubriplate SPO 288 and SPO 299 are specifically engineered for spur-gear and worm gear drives, and are modern equivalents for 600 weight heavy gear oil.

600W seems to be a little confusing - some reference sources define it as "steam cylinder oil", which is a heavy, clinging oil designed to be used in the presence of water. From the data I have read from modern refiners / suppliers, the modern equivalents for 600 gear oil are NOT good for applications which will expose the lube to water/moisture.

Steam cylinder is still available too.

One of the chief "safe qualities" of 600 weight heavy gear oil is that it is safe for use with "yellow metals" ( bronze / brass / copper ). Most modern gear lubes contain sulfur compounds, which attack and corrode yellow metals.

We had this conversation overf in "Yesterdays Tractors" a while ago. Some said the sulphur compounds in GL5, GL4 an GL3 would take out the "yellow metals". I think that the GL1 lubricant was the only one with these compounds. I don't believe GL1 is being made any more. There were some good equivalents. The best I think was a general purpose tractor lube/hydraulic fluid. The Transmission, rear lube and hyd. fluid were all from the same resevior in the early Ford N-series tractors. This fluid, though modern, was compatable with the bearing of the older tractors.
It was similiar to the case "Hy-Tran" oil I use I use in my Case 580E backhoe. I have always wondered if this would work in the Mod A rear. Anybody know?
Terry
 
Aside from Assembly, which it is good for, What's wrong with STP? I've read somewhere it had a "sticky" quality that oil doesn't have. Also, I had a friend who said that engines that were lubed with STP would run longer with out oil than those on straight oil. (Not much longer, but longer) I admit, I never tested it out. But I used STP as an additive for years with
no ill effects. However. It doesn't work in Ford/Mazda 5 speed transmissions. If you have one, DON'T put STP in it. In the case of engines, did I waste my money adding it for all those years?
Terry

STP is not a lubricant. It thickens any oil it is added to. A lubricant is a branched chain paraffinic hydrocarbon. Consider this, the lube oil is diluted by the STP. Does that sound good to you?

Why use STP to thicken (and dilute) a lubricant when lubricants are available that are the proper viscosity(thickness) AND are 100% lubricant?
 
STP is not a lubricant, it is a viscosity modifier[whatever that is].. Personally, I don't want my viscosity modified.. When I was young we did have a number of vehicles come back[ Fords,,, no Studebakers] with defective center mains from lack of lubrication appearing to be from the STP.. We never really recommended its use, regardless of what Studebaker wanted, but some customers wanted it..STP was about the only thing I ever found wrong with Studebaker, hehehe.. A few similar instances occurred when Slick 50 first came out[ we never sold or recommended that crap but some customers would add it]..
As far as adding STP to our tail ends or transmitters, I doubt it would hurt much as long as it was added within reason[ the less the better].. I find they operate just fine however with plain ole 140 wgt. In fact, it appears to me that they seem to be happier downshifting when using the lighter oil, but, that may just be my imagination..
 
This has been debated here before. You will read about the guy that has used straight STP for 10's of thousands of miles with no problems.

I buy mine from the vendors but If I were to rebuild an entire car I would buy yhe 240 stuff and add STP to save on shipping and the cost of the oil.
 
I've used a mixture of 140 gear oil and STP in the differentail for a lot of years; I also use a 50-50 mix in the transmission.

The ring gear in the differentail picks up the heaver STP and keeps it circulating ; the same thing happens with the cluster gear in the transmission.

Ron
 
Thanks for getting back on this. Now I'm a little smarter than I was. This Slick 50 is a scam. Period. Over in Yesterday's Tractors we had a guy, who a tric*****ologist (Friction expert) explain that teflon in an engine was a joke which pretty much agrees with my conclusions about teflon and heat. Thanks again.

Terry



STP is not a lubricant, it is a viscosity modifier[whatever that is].. Personally, I don't want my viscosity modified.. When I was young we did have a number of vehicles come back[ Fords,,, no Studebakers] with defective center mains from lack of lubrication appearing to be from the STP.. We never really recommended its use, regardless of what Studebaker wanted, but some customers wanted it..STP was about the only thing I ever found wrong with Studebaker, hehehe.. A few similar instances occurred when Slick 50 first came out[ we never sold or recommended that crap but some customers would add it]..
As far as adding STP to our tail ends or transmitters, I doubt it would hurt much as long as it was added within reason[ the less the better].. I find they operate just fine however with plain ole 140 wgt. In fact, it appears to me that they seem to be happier downshifting when using the lighter oil, but, that may just be my imagination..
 
hey fellows is it just me or what but the 600w that model a suppliers sell works great and how much do you buy? I change motor oil each 500 miles , transmisson, rearend, steering box maybe once a decade[ a total of two quarts] so the 8-9 dollars a quart breaks down to under $2 a year..... use what we know works and keep driving.... the 500 miles works out to about 3 or 4 times a year pop worded for ford and ford dealers for 60 years had great sucess with his cars he said "the best oil to use is clean oil" which means change early and often and if it has a filter change that at each oil change....
 
I agree with Patrick: STP is a great assembly lube, but it kind of stops there. The major components of STP Oil Treatment are long-chain polymers called VI (viscosity index) improvers, and they are the compounds used to make single-grade (i.e. SAE 30) into multi-grade (i.e. SAE 10w-30) oils. If you add STP to your single-grade oil, you will make it a multi-grade, but with unknown viscosity. I believe the long-chain polymers are what help to stop oil consumption (because they are viscous), but we all know it's a band-aid effect.
 
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