I recently purchased a 1970 LeMans whose previous owner replaced the engine with a '76 455. It hadn't run in 24 years, so I replaced all the gaskets in the engine, rebuilt the carburetor, changed all the fluids, painted the engine, cleaned everything, bled most of the brakes (one of the lines is clogged), but I'm stuck on the simplest thing: a dipstick. He doesn't know where he put the engine oil dipstick for the 455, and I don't know which one to get. I bought a Mr. Gasket 9898, but it's too thick and doesn't bend enough through the tube to fit. The LeMans has factory air conditioning, so that has to be taken into consideration.

P.S. this is my second car and my first classic car (22 year old guy in college)

I heard this forum likes images, so here you go:

Don't have an answer for you on your question but just wanted to chime in and say welcome!

Also, thanks for the pics! We do love them! Congrats on the purchase!

While it appears someone dressed it up with intake, valve covers.  I'm wondering if they replaced the oil pan as well?  To get a ball park length.   Measure from the top of the dipstick tube A, to the deepest part of the oil pan B.  I would use maybe a straightened clothes hanger to get around exhaust.  Measuring from the out side.  Then try to run the hanger down the dipstick tube. My 421 has another tube on the inside that directs the dipstick to the rear so you might not be able to use the hanger but something smaller.  This will give you a guideline to look for a length.  Now we introduce you to classic car 101.......the junkyard.  It's my happy place, but must admit it's been awhile.  You might even have multiple yards in your area.  Your looking for Pontiac's of course and measure a couple dipsticks.  If they are the same length your good to go.  I would assume they would be the same, as Pontiac uses the same block. If it's an aftermarket pan guess the only difference would be the depth of the pan. (adding more oil to the system)  Your full oil line would be 3-4 in above the bottom of the pan. Proud to here kids like you taking an interest in classic cars as you will be the ones keeping the dream alive.  Good luck and keep us up with your progress and any help we can offer. 

Guess there is 2 sizes, one for normal and one for A/C extension.  If you drained, then put in 5 qts of oil (normal oil change)  Then you can measure with the dipstick or make a mark on what you have as oil full.  

You can look online to Frank’s Pontiac Parts in 29 Palms California. I’m sure they have lots of used dipsticks!

14 hours ago, JUSTA6 said:

While it appears someone dressed it up with intake, valve covers.  I'm wondering if they replaced the oil pan as well?  To get a ball park length.   Measure from the top of the dipstick tube A, to the deepest part of the oil pan B.  I would use maybe a straightened clothes hanger to get around exhaust.  Measuring from the out side.  Then try to run the hanger down the dipstick tube. My 421 has another tube on the inside that directs the dipstick to the rear so you might not be able to use the hanger but something smaller.  This will give you a guideline to look for a length.  Now we introduce you to classic car 101.......the junkyard.  It's my happy place, but must admit it's been awhile.  You might even have multiple yards in your area.  Your looking for Pontiac's of course and measure a couple dipsticks.  If they are the same length your good to go.  I would assume they would be the same, as Pontiac uses the same block. If it's an aftermarket pan guess the only difference would be the depth of the pan. (adding more oil to the system)  Your full oil line would be 3-4 in above the bottom of the pan. Proud to here kids like you taking an interest in classic cars as you will be the ones keeping the dream alive.  Good luck and keep us up with your progress and any help we can offer. 

Thanks I'll try those methods! And I appreciate the welcome!

13 hours ago, JUSTA6 said:

Guess there is 2 sizes, one for normal and one for A/C extension.  If you drained, then put in 5 qts of oil (normal oil change)  Then you can measure with the dipstick or make a mark on what you have as oil full.  

I don't have a dipstick though so idk which one to get. Also I put 6 qts in because I think that's what it takes

1 hour ago, Frosty said:

You can look online to Frank’s Pontiac Parts in 29 Palms California. I’m sure they have lots of used dipsticks!

Will do thanks!

16 hours ago, Ringo64 said:

Don't have an answer for you on your question but just wanted to chime in and say welcome!

Also, thanks for the pics! We do love them! Congrats on the purchase!

Thanks!

 

By the way I just got the car driving! Just had to finish brakes to get it back on the road. Drove it with no dipstick though

11 hours ago, Dom L said:

Thanks I'll try those methods! And I appreciate the welcome!

I don't have a dipstick though so idk which one to get. Also I put 6 qts in because I think that's what it takes

Will do thanks!

Thanks!

 

By the way I just got the car driving! Just had to finish brakes to get it back on the road. Drove it with no dipstick though

Local Junkyard motor pile for a stick.  Ask for help if needed.  I don't ever remember adding 6 quarts of oil to a 455.  Seems like 5 qt reads half way on the stick. 6 would be overfilled.  Call a couple of quick oil change places and have them look it up?  They wouldn't give you a drop over the limit. 

If you are keeping the A/C then use ames p/n n306db dipstick tube. the dipstick p/n is n292

not keeping a/c use ames tube p/n n304 with dipstick p/n n290 

the difference is 3 piece with a/c or 2 piece without.

the very bottom tube mounts to the windage tray and is accessible with the oil pan off. and it doesnt matter if its a/c or not.

Hope this helps

On 7/13/2024 at 1:05 PM, indymanjoe said:

If you are keeping the A/C then use ames p/n n306db dipstick tube. the dipstick p/n is n292

not keeping a/c use ames tube p/n n304 with dipstick p/n n290 

the difference is 3 piece with a/c or 2 piece without.

the very bottom tube mounts to the windage tray and is accessible with the oil pan off. and it doesnt matter if its a/c or not.

Hope this helps

Awesome I bought the N292, hope it fits. Thanks!

On 7/13/2024 at 1:05 PM, indymanjoe said:

If you are keeping the A/C then use ames p/n n306db dipstick tube. the dipstick p/n is n292

not keeping a/c use ames tube p/n n304 with dipstick p/n n290 

the difference is 3 piece with a/c or 2 piece without.

the very bottom tube mounts to the windage tray and is accessible with the oil pan off. and it doesnt matter if its a/c or not.

Hope this helps

The N292 just got here, and it's too long and too wide so it doesn't bend enough through the tubes. Maybe the previous owner installed a custom dipstick tube? I can't think of another reason why it doesn't fit....

I may resort to buying a universal spiral dipstick and cutting it

Maybe he did. i have used both the non a/c and a/c one in my car and both worked fine. Is the a/c compressor installed? the dipstick tube is mounted to a bracket that holds the a/c compressor on.

On 7/13/2024 at 11:40 AM, JUSTA6 said:

Local Junkyard motor pile for a stick.  Ask for help if needed.  I don't ever remember adding 6 quarts of oil to a 455.  Seems like 5 qt reads half way on the stick. 6 would be overfilled.  Call a couple of quick oil change places and have them look it up?  They wouldn't give you a drop over the limit. 

Just checked the manual, for a v8 it takes 5qts but 6 if you change the filter.

All pontiac engines...326/455 CID...The external dimensions are the same...The main differences between them is the bore and stroke/cylinder heads...With that being said..Unless the engine has a deeper than stock oil pan (which would require a different oil pump pick up tube)...An easy way to identify an oversized pan..would be to look and see if the pan has side kickouts.. Or if the bottom of the pan is below the crossmember...With the stock oil pan...The oil capacity should be five quarts with the filter...Adding an extra quart of oil to a five quart system will cause the crankshaft counterweights to be submerged in the oil...Which in turn with the crankshaft constantly splashing in the oil...It will cause the the oil to be whipped up into a foam ...Drastically reducing the viscosity/Lubricating properties of the oil leading to low oil pressure and the related issues associated with that...

As far as the dipstick/tube... The difference in the length is related to where the tube  mounting location is and ease of access...Any Pontiac dipstick/tube 326/455 will work ...Just be sure that the tube and the stick are together as a matched unit When getting one off an old engine from the junkyard...