Dipstick tube size for oil analysis sample

[cmatt]

For those of you that have pulled an engine oil sample through the dipstick, what size of tubing did you use? I've tried a 1/4" OD hose with no luck. It seems to hit a hard stop before entering the pan. An image of the dipstick appears to show that it necks down at the bottom. I've got some 3/16" OD tubing on order. Hopefully that will work. I do realize there are products out there to control the oil flow from the drain pain opening that would aid in taking a sample without completely draining the oil, but my preference is to pull from the dipstick.

 

[OR VietVet]

I ran in to this when getting the oil sample from neighbor's 2006 F150 for oil sample to send to Speediagnostix. We had put a new engine in the truck 2 years ago. His truck had the tapered tube and we ended up using 3/16" tubing and it worked fine. Unknown if will be the same for yours.

 

[blanchard7684]

The one that comes with the speed diagnostix kit works in three different late model dipstick tubes I have….

 

[OR VietVet]

I spoke to Lake Speed Jr. personally about the initial problem and he sent the smaller tubing and it fit. He said he now sends 2-3 sizes in kits with unknown sizing but if is 100% sure of sizing, that is what is sent.

 

[WalleyeMikeIII]

Seems like if you measured the diameter of the metal at the bottom of the dipstick, you would have your answer.

 

[cmatt]

3/16" outside diameter tubing worked great.

 

[OR VietVet]

Seems like if you measured the diameter of the metal at the bottom of the dipstick, you would have your answer.

Measuring the outside diameter at bottom of dipstick is a great thought but still does not give the inside diameter of the tube.

 

[WalleyeMikeIII]

Measuring the outside diameter at bottom of dipstick is a great thought but still does not give the inside diameter of the tube.

Correct, but does provide a starting point for what fits.