Correct dipstick 1968 427/390

[George W.]

[Joe L.]

Re: Correct dipstick 1968 427/390

Changed oil and filter -specs called for 6 quarts— is this correct?
Dipstick reading is 1 quart over filled.
Attempting to add photos of dipstick, do not see option for this—working from iphone

George------


6 quarts is correct for all 1965-74 Corvette big blocks assuming the car has the correct oil pan. The correct oil pan has a REAR drain plug. Most other Chevrolet big blocks used a SIDE drain plug. These sometimes end up on Corvettes. It's easy to check.

Correct dipstick should have a white plug on the end of the handle. Otherwise, does the dipstick have a part number embossed on it (on the lower part of the blade)?

[George W.]

Re: Correct dipstick 1968 427/390

[Blair K.]

Re: Correct dipstick 1968 427/390

https://www.forums.ncrs.org/showthre...ion-needed-***

[George W.]

Re: Correct dipstick 1968 427/390

Okay,
It seems that I have the correct dipstick ( the ADD mark is apx. 1 1/2" from the bottom tip of the dipstick)
Reads a full quart over full.
Could the tube be too short?
Does anyone have a measurement for the tube?
Thanks,
G

[Ray K.]

Re: Correct dipstick 1968 427/390

George,

Without pulling the tube from the pan, I have right at 12 & 3/4" from the pan tube lip to the top of the tube . Probably another 1" or a bit more inserted into the pan tube for a total length of approx 14".

Ray

[Joe L.]

Re: Correct dipstick 1968 427/390

George,

Without pulling the tube from the pan, I have right at 12 & 3/4" from the pan tube lip to the top of the tube . Probably another 1" or a bit more inserted into the pan tube for a total length of approx 14".

Ray

Ray and George------


As you know, the important dimension is that from the upper end to the collar which seats on the oil pan's extension tube. The 1965-E67 GM #3862732 and L1967-E1970 GM #3870324 were as mentioned 12-3/4". The late 1970-74 tube, GM #3981089, was 19-17/32" developed length from upper end to collar. These are the only tubes ever used for any 1965-74 Corvette. Any other length tube is incorrect. In addition, the correct dipsticks have to be used with correct tubes in order for the dipstick reading to be accurate.

The GM #3862732 or 3870324 tubes must be used with dipsticks GM #3860316, 3925520, or 3959158

The GM #3981089 tube must be used with dipstick GM #3981088.

George: if you have the correct dipstick and correct tube and you are still getting an inaccurate dipstick reading, then I would say one of three problems are involved:

1) you do not have the dipstick tube fully seated in the oil pan's extension tube, or;

2) you do not have the dipstick fully seated on the tube, or;

3) you have an incorrect oil pan.