DON'T REPLACE YOUR WORKING SENSOR WITH A NEW ONE JUST BECAUSE IT LEAKS OIL. SAVE $$ BY REPLACING JUST ITS O-RING, KEEPING YOUR HIGH QUALITY (and costly) OEM GM/AC DELCO SENSORS.  READ THIS ENTIRE DESCRIPTION.  YOU'LL BE GLAD YOU DID.

(I'm sorry.  EBay is raising their fees AGAIN on March 15. 2024, and I had to raise the price by 15 cents to offset their increased take.  Realize that in the 45 US States that charge sales tax, 20-32.5% of what you pay goes to eBay fees and sales tax.)

REUSE YOUR HI QUALITY LONG-LIFE GM / AC DELCO / DELPHI original OEM sensor.  DON'T THROW IT AWAY (they're expensive) and replace it with aftermarket junk sensors that don't work or fail quickly because you can't find a new AC Delco/Delphi part (or don't want to pay their premium price).   Don't do the job twice because you threw away your leaky but working hi-quality OEM sensor and replaced it with a cheap aftermarket part.  Re-use your high quality OEM sensors, replacing just their o-rings with these, and get a cheaper solution with a more reliable outcome than using aftermarket parts.

2 (Two) brand new, SPECIALTY SIZE & MATERIAL O-RINGS for Camshaft & Crankshaft Position Sensors for GM 4.8L 5.3L 5.7L 6.0L "LS" engines 1997-2009 (see picture for more details). (Won't fit earlier 5.7L "LT" engines having coolant flow thru the intake manifold).  May fit other GM engines & years too...look at the GM and AC Delco part #'s shown in the picture for the GM / ACD sensor part #'s these rings fit.

GM OEM sensors almost never fail…except for aggravating OIL LEAKAGE which is extremely common. These two sensors are the most frequent causes of oil dripping onto your driveway. If you see oil drips on the bottom of the starter motor (especially the starter motor bolts) that’s from a leaky crank sensor. If you see oil dripping between engine and tranny or coming out the end edge of the bell housing (or open the bell housing view shield and look for or swipe your finger and detect engine oil), that’s most likely from a leaky camshaft sensor (don't despair...odds are it's NOT the rear main seal.  I learned this the hard way, pulling the engine to go after the rear main seal, only to see after the engine was out that my leak was from the darn cam sensor...I also had the crank sensor leak that shows up on starter motor & its bolts.  The lesson: it's far easier and cheaper to FIRST try these o-rings and see if they fix your leaks.  They did for me.

They leak oil because the O-rings in these sensors deform and flatten, causing seal failure.  The O-rings the factory used most often, that are prone to this failure, are BLUE.  They are a softer material than these brown rings (durometer 70 instead of 75).  Also, the cord dimension (cross-section thickness) of the blue rings is .01" thinnner than these brown rings (based on manufacturers' specifications) making their diameter .02" smaller.  Because the blue ones are softer and slightly too small, they fail routinely and early.   It's why every GM 4.8L, 5.3L, 5.7L, and 6.0L "LS" engine starts leaking oil out these sensors early in life.  The factory used the blue ones likely because they are cheaper.  The slightly harder material of these brown rings, plus their slightly larger dimensions (along with superior temperature tolerant material), combine to give a much better, tighter, longer lasting seal.  You can feel the difference when you install it.

Now you could just buy a whole new CHEAP aftermarket sensor.  BUT...Just as with GM knock sensors, GM PCU’s are very sensitive to electrical signal characteristics coming from all these sensors involved in ignition timing (i.e., cam & crank position & knock). Ever done the troublesome knock sensor replacement using aftermarket sensors, only to have them trigger your check engine light the first time you drive on them?  Happens almost every time aftermarket sensors are used...notorious for this.  Big troublesome job you get to do all over again.  Well, MANY cheap aftermarket CAM/CRANK sensors will trigger the “Check Engine Light” the same way.  Read some of the product reviews on these o-ring ads I've placed and you'll see folks who suffered this exact experience, and you'll also see posts by professional mechanics warning how darn "picky" LS engines are with any of these sensors associated with ignition timing.  Read the reviews of the cheap sensors and see the failure complaints.  Unless you're OK with a high probability of doing the  whole job over again, it’s best to use original GM, AC Delco, or Delphi sensors, which are much more expensive than aftermarket...because THEY WORK, they're much higher quality, and last way longer. But if your sensors are good yet just leaking, it’s cheaper by-far to simply reuse your high quality OEM sensors and just replace their O-rings with these higher quality, better fitting brown rings.

It’s aggravating GM DIDN’T SETUP A PART# for this O-ring. They force you to buy entire sensors. GM doesn’t offer (nor does anyone else) a replacement 0-ring. And to make matters more difficult, GM used a NON-STANDARD SPECIALTY SIZE 0-RING! O-ring sizes are universally defined by a standardized “DASH” specification, but no standard DASH size in that spec will fit these sensors. If you mistakenly try using the closest standard DASH size (the size you may read about on the internet), your engine will leak like JULIAN ASSANGE!   They are way too loose and you can readily feel its definitely not right.  And on top of the frustrating difficulty of finding the proper size, there’s also the difficulty of finding a reliable material that’s both high-temperature and oil tolerant.  After burning a lot of time hunting for obscure sizes and exotic materials, and trying many alternatives that failed, I found these O-rings are a perfect fit and material…GUARANTEED. If only one of your sensors is leaking, the other isn't far behind, so I'm selling a pair of O-rings so you can do both sensors.

[Often the selling of low priced, low volume items like this on Ebay does not seem worth the hassle.  So, realize:  the TOTAL PRICE of rings PLUS SHIPPING cost is what I need to make dealing on eBay and with eBay, worth that hassle.  But to help many buyers, I designate a chunk of the total price to be in shipping because, in 22 US States that exempt shipping costs from sales tax, this lowers BOTH sales tax AND EBAY FEES TOO (which buyers ultimately pay).  This is because eBay applies their fee% not just on the sum of (item price + shipping), but also on the sales tax they collect too (which is not well known) !  Hence, for low priced items like this, by applying their fee% to sales tax, this drives up their total fee to 18-19% of (item+ship) cost.  But, by designating a chunk of the price in shipping, this lowers sales tax and eBay fees in 22 US States.  If you are inclined to complain to eBay about the shipping costs quoted in the ad, or leave a negative review largely due to shipping cost, please don't make the purchase.  

Also realize, State + local sales taxes range from 2-13.5% among the 45 US States that charge sales tax.  So in those states, 20-32.5% of what you pay goes for Ebay fees and taxes.  Thank you. ]