1955 buick roadmaster-motor oil

[Guest j.w.]

good am folks,

my 55 roadmaster,322 nailhead v8 needs an oil change. i understand that one must use zinc containing oil.can someone recommend an oil w/ zn/phosphorous content in the 1300-1400 range. also not sure what viscocity to buy or to buy a detergent vs non dtergent oil. i know there are a few products out there containing zddp(is an additive).,but i wish to buy oil which has proper content.

also does anyone know what the content of zdpp in a container of stp-i may have to use this instead(AS AN ADDITIVE TO OIL)

thanks for all the help.

[old-tank]

This has been discussed before: http://forums.aaca.org/f115/zinc-motor-oil-338283.html

While extra zinc will not hurt, you probably don't need it.

Willie

[bhambulldog]

I use Valvoline 30w and add STP Oil treatment with ZDDP

Or I use Shell Rotella 30w with the ZDDP already in it (it's for diesel engines)

EDIT: Rotella single grades no longer have ZDDP

Edited July 18, 2013 by bhambulldog
correction (see edit history)

[64Riv-King]

I use Brad Penn. Made in America from Pennsylvania known for high quality sweet crude. Many different grades to choose from with the proper levels of zinc. Here's a link to their website. Welcome!

[Guest gunjeep444]

I saw and ad in Hemmings Classic Car magazine , they are selling oil with extra zinc in it.

[RivNut]

Mobil 1 15w-50 full synthetic has the zinc and phosphorous that these cars need w/o adding any additives. One of the nice things about it is that you can buy a 5 quart jug at Wally-world for less than $25.00. If you go to the Mobil website you can find a chart that shows the levels of zinc and phosphorous in everything they produce as well as recommendations.

Ed

[michel88]

I would be hesitant to put synthetic oil in an old engine that has not used it before. I have read articles that synthetic oil can leak through seals and gaskets that the conventional oils do not. If you develop leaks they will still remain even if you switch back to conventional (non-synthetic) oil. I would not put a synthetic oil in your 1955 Roadmaster.

[Ron Green]

One of the most opinionated subjects in the old car hobby.

I have been running Mobil 1 synthetic in my 55 Pontiac (and all my old vehicles) since 1994 with zero issues and the engine has 74K original miles and never been apart. In my opinion all carbureted vehicles will put a certain amount of gas into the oil and synthetic can handle this better than conventional oil, including the acids from the combustion process, plus they take the heat and cold better than conventional oils. They corrected the leaking seal issue 20 plus years ago. In reality you really don’t need the zinc, again only my opinion and a lot of oil engineers.

Zinc in Mobil 1: http://www.mobiloil.com/USA-English/...duct_Guide.pdf

[michel88]

My advice on not using synthetic oil in older engines seems to be wrong according to what I am reading on the internet. Early synthetics were made of esters which were harder on seals especially those made of neoprene. Since the 1970's they have come a long way and now synthetic's are much nicer to delicate seals. I know synthetic oil is better than conventional oil but I didn't know that the leakage problems have been solved. I have been using it in newer engines right from the start but now I may try it in my old cars too. From what I have read Amsoil seems to be considered the best synthetic oil, but also the most expensive.

[old-tank]

Woody

That 55 had rope seals anyhow:p.

[bhambulldog]

My advice was rotella 30w

It's been brought to my attention that Shell has lowered the ZDDP in 30w Rotella

It seems that one needs to research before every oil change

Edited July 18, 2013 by bhambulldog
speling (see edit history)

[Guest Straight eight]

Only the single weight Rotella 30 weight was changed. The 10-30 and 5-40 the multi viscosity oils now have zinc according to Shell.

>> From: <shelltechnical-us@shell.com>

>> To: <alglen@comcast.net>

>> Sent: Thursday, December 20, 2012 9:36 AM

>> Subject: Re: 1947 Buick Super Convertible

>>

>>

>>> Hello Mr. Herold,

>>> You are correct, the Rotella T mono-grades were reformulated a

few

>>> years ago and the new Rotella T1 mono-grades are not rated for

>>> gasoline engines and now have lower zinc levels than before.

>>>

>>> We recommend using the multi-grades, Rotella T w/ Triple

Protection

>>> in which ever grade you prefer. The multigrades have more zinc,

1200

>>> ppm, (and are rated for API SM for gasoline engines) which has

proven

>>> to be sufficient for older cars with solid lifters.

>>>

>>> Best regards,

>>> Keith Perry

>>> Shell Technical Information

>>> 800.237.8645 Opt 31

>>>

Edited July 17, 2013 by Straight eight (see edit history)