1970 454 dipstick length with a.c.

[G B.]

The Judging Guide says: "All dipsticks, or gage handles, are formed round tubing with a colored plastic plug in the end. 1970 Mark IV engines have a black plug, 1971 and 1972 have a red plug. Mark IV air conditioned cars have a dipstick and tube that is about 4 inches longer than non-air conditioned cars."

My September, 1971 Chevrolet Parts Catalog lists only one dipstick for all 1969 through 1972 big blocks, #3981088. It is shown as having a dimension of 24" from the cap to the add mark. It is still available.

The aftermarket Corvette supply catalogs also list only one dipstick for 1970 big blocks. They do not specify the length. The Paragon catalog does say that theirs has a red plastic plug, however.

Would someone please give me the benefit of their experience on this. What length dipstick (cap to add mark) do I need for a 1970 454 with a.c.? Who sells such a dipstick length if not GM?

[Joe L.]

Re: 1970 454 dipstick length with a.c.

Jerry-----

There were 2 different dipstick/tube assemblies used for 1970 big blocks. However, as far as I know, A/C was not the determining factor in which one a car receieved. Early 1970 big blocks used dipstick GM #3959158. This dipstick was used with dipstick tube GM #3870324. Later 1970 Corvette big blocks (and all 1971-74 Corvette big blocks) used dipstick GM #3981088. This dipstick is used with dipstick tube GM #3981089. The above-referenced dip stick and dipstick tube assemblies CANNOT be interchanged. That's because the 3981088/3981089 are longer than the 3959158/3870324. The increased length may have been done to better accomodate A/C applications, but it was not used exclusively for A/C applications. It was an "across-the-board" type thing after "mid" 1970.

The 3981088/3981089 will SERVICE all 1965-74 big blocks as long as BOTH parts are used. However, the 3981089 tube is discontinued and no longer available from GM.

[Joe L.]

Re: 1970 454 dipstick length with a.c.

Jerry-----

There were 2 different dipstick/tube assemblies used for 1970 big blocks. However, as far as I know, A/C was not the determining factor in which one a car receieved. Early 1970 big blocks used dipstick GM #3959158. This dipstick was used with dipstick tube GM #3870324. Later 1970 Corvette big blocks (and all 1971-74 Corvette big blocks) used dipstick GM #3981088. This dipstick is used with dipstick tube GM #3981089. The above-referenced dip stick and dipstick tube assemblies CANNOT be interchanged. That's because the 3981088/3981089 are longer than the 3959158/3870324. The increased length may have been done to better accomodate A/C applications, but it was not used exclusively for A/C applications. It was an "across-the-board" type thing after "mid" 1970.

The 3981088/3981089 will SERVICE all 1965-74 big blocks as long as BOTH parts are used. However, the 3981089 tube is discontinued and no longer available from GM.

[Terry M.]

[Terry M.]

[G B.]

Unique printing?

I'm using a Third Edition of the 1970-72 Corvette Technical Information Manual & Judging Guide that Eric mailed to me about two months ago.

Please confirm that I have the only copy with the sentence on page 67 that says: "Mark IV air conditioned cars have a tube and gage that is about 4 inches longer than non-air conditioned cars". If so, I'll put this sucker on eBay and try to sell it for big bucks as a one-off.

[G B.]

Unique printing?

I'm using a Third Edition of the 1970-72 Corvette Technical Information Manual & Judging Guide that Eric mailed to me about two months ago.

Please confirm that I have the only copy with the sentence on page 67 that says: "Mark IV air conditioned cars have a tube and gage that is about 4 inches longer than non-air conditioned cars". If so, I'll put this sucker on eBay and try to sell it for big bucks as a one-off.

[Terry M.]

No big $$ *TL*

Sorry Jerry - no big bucks for you, but egg on my face. I didn't read far enough into the paragraph and when I came up with your first sentences and not the last I thought your version was different. My bad.
So now we have to see what the car owners have to say. No one ever said this would be easy.

[Terry M.]

No big $$ *TL*

Sorry Jerry - no big bucks for you, but egg on my face. I didn't read far enough into the paragraph and when I came up with your first sentences and not the last I thought your version was different. My bad.
So now we have to see what the car owners have to say. No one ever said this would be easy.

[Roberto L.]

Re: 1970 454 dipstick length with a.c.

Terry, second edition mentions that difference in AC vs non AC cars.

4 inches.

Roberto, NCRS #30019, RMC

[Roberto L.]

Re: 1970 454 dipstick length with a.c.

Terry, second edition mentions that difference in AC vs non AC cars.

4 inches.

Roberto, NCRS #30019, RMC