GM EOS

[bentvalves]

30 bucks for a 16 oz bottle?

on freshly built engines I dump oil once engine gets up to NOT for the first time.

I was hoping this EOS was going to be a magic bullet, but at 30 bucks it doesn't make sense.

anybody know where to get it at the right price?

are you folks doing anything special for roller cam engines in terms of zinc or additive or break in oils?

happy new year everybody.

[Schurkey]

Any time I fire a fresh engine, I install a Frantz asswipe bypass oil filter. The filter may not stay on past the first 500 or thousand miles; sometimes it's permanent.

Amsoil also sells a bypass oil filter assembly.

With the bypass oil filter, there's zero need to change oil right away, the bypass filter removes all the wear particles so the oil is kept clean. There is still a need to replace the full-flow filter at ~20 minutes if you've used heavy moly paste on the cam 'n' lifters.

Any expensive additives you put into the expensive break-in oil can last for thousands of miles of use...because there's no need to dump oil to remove wear particles and contaminants. Just top-off when the full-flow filter is changed.

[ProPower engines]

30 bucks for a 16 oz bottle?

on freshly built engines I dump oil once engine gets up to NOT for the first time.

I was hoping this EOS was going to be a magic bullet, but at 30 bucks it doesn't make sense.

anybody know where to get it at the right price?

are you folks doing anything special for roller cam engines in terms of zinc or additive or break in oils?

happy new year everybody.

If your trying to cheap out on the break in oil then it will bite you hard sooner then later. There is no good deal on that stuff unless you find a guy with an open can that was done by mistake even then maybe.
There is several good break in specific oils to choose from and many good options for the best oil choice for the cam type your running. While engines all need some anti wear additives a roller can get by with less but its not a thing I would ever take a chance on. Any of the cam suppliers will not talk to you if your not using their break in oil or a respected break in oil. The days of using EOS do not make any sense with better options in oils.
It's the hardest part to get guys to change away from the old EOS to a break in oil because the additives are blended in the bottle when you pour it in. EOS blends at some point after the engine has ran for an hour.

But if a DIY guy wants to chance it that's on him. I would never chance it when there has to be a warranty of some type and a good number of oils suited for the task .

[Krooser]

I am hoarding several bottles of the old school EOS... I like to pour it on the lifters and cam just before I button up the intake and fire the engine for the first time.

Does the new EOS have any zddp in it?

[BillK]

I havent seen EOS in 20 years ::) I just use one of the dedicated break in oils also. I don't remember if it was at PRI or somewhere else but we went to an oil seminar and were told that it is always better to use an oil that already has the correct additives in it. They said that sometimes the stuff that you add can actually react with the factory additives and make things worse.

[CGT]

You should be able to find EOS for 20.00 or less. It has a dealership cost of around 16.00. But, I question whether its the same product that it used to be.

[rebelrouser]

I have not used GM EOS for years, but years ago I used to make assembly lube by mixing EOS and 40 weight oil and put it in a squirt can, seemed to work well. I knew a guy who worked for BG products, and he actually showed me a chart that tested oils after they had been mixed with BG additives. All the oils improved, but it was not consistent brand to brand. Some oils only showed slight improvements. And I have seen a goo in the bottom of the pan from additives that did not mix, they just sit in the pan. I am not a big fan of additives, I agree run the oil that works in the engine, and use an assembly lube to protect at startup.

[Schurkey]

Does the new EOS have any zddp in it?

Define "new" EOS.

Here's the MSDS for AC-Delco 10-4021; which is cross-listed as GM 88862587. Prepared 01 June 2015.
http://msds.fmpco.com/images/fmp_msds/1 ... ricant.pdf

Phosphorodithioic acid, O,O-di-
C1-14-alkyl esters, zinc salts
68649-42-3
5 to 10%

So I'd say "yes", there's plenty of ZDDP or similar zinc-phosphorous compounds as of 2015.

[Dave Koehler]

A little EOS trivia.
I used to buy it by the case from Chevy.
One day upon opening a new case a couple of the cans looked different.
Pulled them out and lo and behold it was Mopar branded.
I forget what Mopar called it.
Hard to say how may other companies sold the same product.
From that point on I called both places to see who had the best case price.

[CamKing]

This is what I recommend and sell, for engine break-in.
https://penngrade1.com/products/high-pe ... il-sae-30/

Run it for the first 200-500 miles in a street performance application, and for the first couple of weekends in a circle track application.

After that, I recommend switching to their monograde of partial synthetic oil.

[ProPower engines]

It still come down to educating the mass's to use the correct oil!
Until the EOS stuff is no longer available guys will continue to read forums and believe its the end all to save cost
over just buying the correct oils. Years ago when oil had additives in it the EOS was just a bandaide on GM cars to help keep a cam and lifters in them till the warranty was over. Its been around for donkey's years but I remember a shop I worked at in the 70's getting a service bulletin about cam and lifter failures on out of warranty vehicles that stated if the owners choose to go to other service options other then at their GM dealer and failed to ad the GM EOS additive acm/lifter issues would result.
Just to say how bad it was we serviced a private security company that had a fleet of 75 Nova's and with in 3 months of out of warranty service at the shop I was at we started to see cam failures . They had a 30K warranty and they would be over that in a little over year's time. We used the same oils as the dealership did at the time it was Quaker State oil and the only difference was that can of the GM EOS additive was added at the time the oil was changed. The dealer at the time was charging a little over $100 for the oil change lube and tire rotation etc.
The local dealers supplied us with the TB about a year later and they kept it a BIG secret because of law suits for the sales dept. not telling customers that if they did not go to the local dealer for service for the life of their vehicle that the result would be engine component failure and large repair costs.

[pdq67]

I have used EOS through the years on rebuilds AND I always use something like Isky's, "REV-Lube", moly paste on the lifter bores, faces, P/R's and seats and rocker balls!

I also put it on all cam lobes including the F/P lobe!

Has always worked good for me.

Plus, I change out the filter after a couple to three heat cycles like driving easy back and forth to work over a week. Then I usually cut my filter open and have a look.

Oh, and BTW, I have used Walmart oil for years and years. Their, "Tech 2000", oil and a good oil filter. I thought I saw where, "SF", oil was being sold again, but don't know if it is really formulated like the old oil that we used for years before oils got marketed!!

I hope that new SF oils are supposed to have ALL the old stuff in them like way back then???

As stupid as this sounds, I remember when our OLD oils smelled more like 90wt gear lube because of the additives in them!! And had that dark, green(??) color....

pdq67

[Krooser]

I remember seeing Ron Neal from Prototype Engineering (built a ton of ovaltrack engines in the 80's) at the Dave Dayton Thanksgiving Racers Auction giving a through look see at Chevy blocks going thru the auction.

He told me he was looking at the cam tunnels to try to find the best candidates for a race engine. He said GM built thousands with cam tunnels that were not machined parallel to the crank... maybe due to core shift? Killed camshafts in short order.

First indication was an oval or offset machined surface at the front of the cam tunnels.

I always look for that whenever I see a SBC block...not many aftermarket blocks 40 years ago.

Working at Chevy dealers in the 60's I saw most of our mechanics use EOS with every other oil change...

[ProPower engines]

I remember seeing Ron Neal from Prototype Engineering (built a ton of ovaltrack engines in the 80's) at the Dave Dayton Thanksgiving Racers Auction giving a through look see at Chevy blocks going thru the auction.

He told me he was looking at the cam tunnels to try to find the best candidates for a race engine. He said GM built thousands with cam tunnels that were not machined parallel to the crank... maybe due to core shift? Killed camshafts in short order.

First indication was an oval or offset machined surface at the front of the cam tunnels.

I always look for that whenever I see a SBC block...not many aftermarket blocks 40 years ago.

Working at Chevy dealers in the 60's I saw most of our mechanics use EOS with every other oil change...

GM blocks were among the worst for machining tolerances. They bore the cam bearings in the block making the cam in the correct location till the bearings are changed.
I can't count the number of times I have had to machine #3-#4 bearing bores larger to get a correct ID for the cam to slide in a block yet it ran with the same journal size for 20 yrs before that.

EOS was GM's answer to saving there engines from cam+lifter issues from there less then perfect machining.And always part of the dealer service protection package they called it here because they just knew without it they would be replacing cams+lifters all the time which would dramatically affect vehicle sales sooner then later.
I bet I can count on 1 hand how many ford or dodge engines came in with a flat cam in 10 years I was there at the shop.

Thats why BHJ came up with the lifter true set up to fix that issue for serious builders.

[Alaskaracer]

I can't count the number of times I have had to machine #3-#4 bearing bores larger to get a correct ID for the cam to slide in a block yet it ran with the same journal size for 20 yrs before that.

I ran into this on my very first BBC build....Couldn't figure out for the life of me why the cam didn't fit in the block....I ended up sanding down the bearings to fit.....I was young, stupid....but that engine ran for a total of more than 250,000 miles before I retired it!!!

And I never used anything in the oil but plain old oil.......flat tappet cam too.....