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Given a stock-ish engine and you believe the 67 service manual...

View attachment 153455

I used to run conventional 10w40 in all my stock-ish V-8's, but have since changed to Rotella 15w40 (because like the smell better)...lol

Your engine build could like a different weight and that is something you should talk to the builder about.

Here we go again with the oil pan fill mis-information. :mad: Read this:


6,426 Posts
My '65 389 holds 6 quarts with the filter. Original pan and dipstick. My '67 GTO holds 7 quarts with filter. Original pan and dipstick. I use the long Wix filters and Shell Rotella 15/40 diesel spec oil, and have since about 2002. Prior to that, it was Kendall 10-30, no longer available. Run a high zinc/phosphorus oil like the diesel spec stuff, or the classic car stuff. Racing oil does not have the additive package needed for stop and go street use, nor the anti-corrosives. It's made to be run hard at the track and dumped.
If I were in a colder climate, I would run more expensive 10-30 high zinc boutique oil like Brad Penn. As hot as it is where I am, however, the 15/40 has been just fine. Many folks like to specify really heavy 20/50 oil, but for an engine that's set up to stock specs and not worn out, it's a bit thick.
I don't run synthetic oils in any of my old cars, and haven't in the 40+ years I've been driving them.
Just for fun, the next time you change oil in the '67, only put 5 qts in the pan. Then remove the dipstick from the '65 and check the oil fill level. If both pans are the same, and have the same capacity, the 5 qt dispstick will read Full with the 5 quarts in the '67 pan. This would mean that the 6 qts is 1 qt over full and your '67 has a 5 qt pan + 1 filter for 6 qts.

I am sticking with a 5 qt pan and 1 qt filter, but always fill to the full line after you run the engine as some filters are larger/smaller.

The SD 421's used a higher 6 Qt capacity pan. I emailed Butler about this as they rebuild a lot of engines, and the reply was that they did not see any differences in the pans and thought they were all the same capacity.

And, in all the engine build books, including some golden oldies, none of them recommend or mention to find the 1-year only 1967 GTO oil pan because it holds 6 qts of oil versus the standard 5 qts.

The question of oil and filter capacity has been asked a couple times here in clarifying the correct amount. The confusing part is that some will say 5 quarts in the pan plus 1 for the filter making it a 6 quart system. BUT, another person may say that the correct amount is 6 quarts in the pan and 1 for the filter making it a 7 quart system - and they would be right based on the year of their GTO. This conflicting info deals with the 1965-67 model years.

With the introduction of the 1968 model, all Pontiacs use 5 quarts in the pan and 1 quart for the filter.

A service bulletin was issued by Pontiac in 1966. It clearly states that the oil capacity is 6 quarts in the pan and 1 quart in the filter. GTO owners will tell you that their dipstick clearly says 6 Quarts at the fill line - so yes, this is fact, according to the Service Bulletin, but maybe there is a reason for such a bulletin and it may not be because a larger pan was used. Yet when a 5-quart dipstick is set side-by-side with a 6-quart marked dipstick, they are identical in length. There is no difference in the pan, they are all seemingly the same. Hmmm, so what gives?

An earlier problem with low oil pressure in the 1961 421CI HO engines was noted by a PY member and falls in line with the later GTO problem and the 6 qt pan fill:

"A couple months ago I was reading the Craftsman Service News, and found a recommendation for a 421 HO that wanted you to put in an extra 1/2 Qt and make a new full mark on the stick. Reason was accelerating hard may cause a loss of pressure."

A PY forum member stated that he had talked with Milt Schronack of Royal Pontiac fame and he stated that Pontiac was replacing a lot of 1965 GTO engines under warranty and it was found that the engines were being burnt up due to lack of oil. The owners were pushing the engines hard and at the upper RPM's much of the oil was being pumped up to the top end and not leaving enough in the pan to oil the bottom end - especially if the oil level fill level had been allowed to get low. So Pontiac issued a service bulletin to fill all engines with 6 quarts plus 1 quart for the filter. They also used a dipstick having the 6-quart fill mark. This extra quart helped keep enough oil in the pan and prevent the engine from running out of oil and burning up.
So this bulletin and change was for 1966, but owners of 1965 and 1967 GTO's have also found the 6-Qt stamped dipstick. It is quite possible that when the car was brought to a dealership to be serviced and the oil/filter changed, the 5-Qt dipstick was replaced with the 6 Qt stamped dipstick so as to protect Pontiac from having to cover warranty engine work.

PY member response:
"However, it may be up to interpretation: Nobody runs w/o an oil filter. The indicator says 6 QTS, that would be with oil filter mounted. Drain the pan, change filter, pour 6 QTS in total and check indicator.
Have the same 5qts stick as you posted , also have one marked 6qts. same identical length just scaled up higher."

PY Member Pinion Head:

"All the Pontiac V8 non-AC indicator rods I have noted are 17 3/16" from the tip to the bottom of the Bell shaped cup that covers the tube.

First version I have is inscribed "- DO NOT OVERFILL - USE GM MS OIL "
this style, I believe, is earlier than 64.

2nd style here is is inscribed 5QTS-DO NOT OVERFILL- USE GM -60641-M QUALITY MS OIL
believe from parts I pulled with it, that version is '66-67.

The non AC indicator rods marked " - 5QTS - DO NOT OVERFILL- USE SE ENGINE OIL" are '68 & later.

Am measuring 3 3/16" inch to the full line on all of the above versions."

Another Pontiac pan/dipstick oddity in 1964 as noted by a PY member, "But in '64 everything got the same pan (4-qts) and upper tube. 389, 421, HO and GTO all got the same pan and upper tube but the 421, HO and GTO (were to get 5+1 of oil) got a different dipstick to measure the difference." In other words, the 4-qt pan was overfilled 1 qt and Pontiac used a differently marked dipstick to show 5 qts in a 4 qt pan.

If I ever get the chance to purchase a known 1966/67 GTO factory oil pan at a reasonable price, I will get it and measure its dimensions and fill it with oil to confirm the actual oil capacity. (y)

6,426 Posts
As Jim mentioned above;

Pontiac Service News Flash number 64-16 (10-18-63) and 65-53 (12-22-64) verified that the oil capacity on all Pontiac V-8 should be five quarts - six quarts with filter change. Some 1964 models were manufactured with a four quart dipstick; the five-quart dipstick , part number 9776085 (code MF), should be installed.

Also 389´s used a longer oil filter, at the time, with approximately 50 percent more oil in it than oil filters on 1967 and later engines.
I leafed though an older Chilton's Repair book (not always the most accurate) that covers all car models and a span of certain years, and under the Pontiac section, all the 1955-63 engines show 5 quarts in the pan +1 for filter. However, is shows only 4 qts in the pan and +1 for the filter for the 1964 year model which mirrored the PY member's mention of all 1964 cars having the 4 qt pan - which seems odd.

My AMA Specs for 1964 full size does show 4 qt pan +1 filter and the optional 5 qt pan +1 filter for the Optional 421 engines. The Tempest models also used a 4 qt pan.

1965 AMA Specs show 5 qt pan +1 filter.

1966 AMA Spes show 5 qt pan +1 filter BUT, read the clipping below.

1967 AMA Tempest Specs (8-26-1966) show 5qt pan +1 filter AND 6qt pan +1 filter for the Option Engines on the Lemans/Tempest Safari, and GTO. Optional engines are listed as the 400 HO and Ram Air 400. Firebird Specs (12-23-1966) show 6 qts pan +1 filter for Firebird 400 and Ram Air engines, and AMA Specs for B-Body engines show 6 qts pan +1 filter.

1968 AMA Specs are back to 5 qts pan +1 filter for all models.

There is an NOS oil pan for the 1964 389/421 engines on Ebay. Seller states it is a rare 1 year only pan. Couple pics of this pan.

Font Newspaper Document Publication Paper product

Tire Artifact Gas Natural material Wood
Artifact Rectangle Gas Metal Font
Rectangle Wood Gas Dishware Artifact
Gas Wood Font Rectangle Pattern

6,426 Posts
Hi Jim. My '65 and '67's both have their original pans and dipsticks. As you know, I've had both cars 40 years. I have never thought about comparing dipsticks between the '65 389 and '67 400, but now you have me curious if they are even the same length. Here's a couple of shots from the original owner's manual from my '67, verifying the 7 quart fill. The 389 in my '65 does not take 7 quarts. I think it's 6 with filter. View attachment 153569 View attachment 153570

Not doubting the manual and certainly not the dipsticks that are clearly stamped 6 qts. The AMA specs as I pointed out for 1967 say 6qts +1 for the HO and RA engines - which may be carry over thinking from 1966 when they had dealers add the extra qt and changed the stick to 6 qts. An extra quart is really not going to hurt as oil hangs up throughout the engine when its running.

Do the check using the '65 dipstick and 5 qts only in the '67 pan and lets see what the reading is. I pulled up some more Pontiac Parts numbers/years right from the 1975 Parts Book I have on CD.

I have a parts cross-reference book that says only 3 oil pans were used on the GTO with the book only covering up to 1972 - 1964 #9773322, 1965-71 #481030, 1972-75 #490766/#527503 which has the baffle and a NOTE: WHEN USING ON SOME 1973 EARLY JOBS DO NOT DISCARD EXISTING BOLTED ON TYPE OIL BAFFLE, AS THIS RETAINS THE OIL LEVEL TUBE /SUP #485339. I suspect the 2 different part numbers are for the rear oil pan seal type used as they changed, not the overall pan.

Also show Pan #1525745 - 1976 350 OR 400 PONT ENG — 1ST
TYPE Ran #1527503 - 1976 350 OR 400 PONT — 2ND TYPE —

Dipstick Part #
1964 - two V8 dipsticks. The 4 Qt. #9773411 and the 5 Qt. #9777125. A/C did not affect the choice of dipstick. 326 Tempests, 2 bbl & 4 bbl 389 big cars were supposed to get the 4 Qt. Reading. The big car tripower 389 & all 421 equipped big cars plus all GTOs were supposed to get the 5 Qt. Reading. Due to a production error some very early GTO's got the 4 Qt. Reading.
1965 - #9777125
1966 - 1967 #9777951 - ALL 8CYL-EXC. AIR CONDITIONING
1967 #9789240 - ALL 8 CYL - WITH A/C
1968 - 1976 - #9793342 - Overall Length 19 3/4" - ALL 8CYL-EXC. AIR CONDITIONING
1968 - 1976 - #9793341 Overall Length 31 1/4"- ALL 8 CYL - WITH A/C, EXC. 1970 RA3 w/AC & 1971 455 HO w/AC
1971 - #483766 Overall Length 32 1/4" - A-body 455 HO w/AC

Upper Engine Dipstick Tube:
1967-1973 & 1974 455's - #9795830 - ALL 8 CYL - STRAIGHT 9-1/8" LONG /SUP 523707
A/C upper dipstick tubes have several part numbers over the various years.

Here is a good example of reading and not fully understanding the printed page:

"Question - I have a 72 Lemans with 455ho. Service and owners manuals all state oil capacity is 6 quarts. Dip stick says 5. According to dipstick its full at 5. As far as I know engine is stock. Wondering if the wrong dip stick got put on engine somewhere along the way.

Answer - Most Pontiac V8's have a 6 quart total oil capacity - including the oil filter, your '72 455HO included."

6,426 Posts
OK Jim....I checked both my dipsticks and here's the skinny: the '65 389 is 25" long from tip to ferrule, and the tube runs up along the valve cover. It says "Capacity 5 Qts. Do Not Overfill". The '67 does NOT run up along the valve cover....rather it comes out of the block and the loop is at the top of the head. So the tube is much shorter. The 400 dipstick is 17" long from tip to ferrule, and it says "Capacity 6 quarts Do Not Overfill"
So the '65 takes 6 quarts with the long filter or a bit more, and the '67 takes an additional quart. Both engines are non AC and have original dipsticks and pans from day one.
Swapping dipsticks would show nothing since the tubes are 8" different in length.
Hmmm. Where is the Full mark on the '65 dipstick if you marked a point 8" lower (at 17") to equal that of the '67 and then measured from that point to the Full mark. Do the Full lines now match up or is the '67 Full mark a quart higher (using the space/distance between Add and Full to determine the extra qt?).

How about from the base/tip of the sticks to the Full mark. The same distance?
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