Lonestar

Vehicle- 2002 Chevy Pickup 2500 HD 6.0L 4x4

There is some sort of bolt on the rear of the engine oil cooler line assembly (above the oil filter) that is visibly leaking. What is this and can I replace the o-ring or seal on this bolt without replacing the whole assembly? See attached pic.
Oil cooler line pic.pdf

02HD

I have same model and engine with the same problem, what did you do to stop the leak ?

02HD

Anyone replaced the oil cooler lines before. Theres little room to see if this is an actual bolt head although it does look to be interior hex. If it is , is there an o ring?
OEM at rockauto is about 90.00 to replace the line set. Alot to spend if I only need an o ring.

02HD

Well after no replies I decided to go ahead and replace the line. For anyone else having this leak. Takes about an hour to complete if all goes as planned. The bolt on the end of the aluminum block is indeed threaded with an O ring. If thats where your leak is. Gasket and an O ring should get you going without the added expense and time. Hope this helps someone in the future.

Patrickg2017

Do you know what size hex and O ring gasket. Is there a flat gasket at the back of the bolt head? I just replaced my block to oil cooler line gasket, to find that the bolt is leaking.

Boarslab

I staggered across this forum while looking for a fix for my leaking oil cooler line on my 5.3l GMC...I had the same problem as the rest of you with the plug on the oil cooler block leaking...I had already replaced the oil cooler line block gasket, but it was still leaking around the plug that has the hex/allen indention in it...Here's how to fix it without having to buy the oil cooler line and replace that whole thing...this is a .25 cent fix. First, you have to take the U joint loose and move the front differential drive shaft to the side so you can get to it..take the 2 10mm bolts out of the oil cooler line block (that gasket will then fall down and you can replace it or just put it back in if it's not leaking--about $8 if you replace). Then, you can take your hand and kind of move the block down so you can get to the Allen/hex plug--it will screw out, but make sure you don't bend the lines--you'll have to hold them with your other hand.. This ALLEN HEX IS A 3/8 th's inch ALLEN. The plug has an O ring that will prolly be hard or broken--just use a pick and take it off and replace the O ring--any local parts store will have it...You can also use just a round or two of teflon tape on the threads of the plug for insurance.. Replace the plug making sure you use both hands to not bend or kink the lines--won't take much to tighten it down either... It is not a flat gasket either--it is an O RING...To sum it up you'll need: 3/8ths Allen wrench or Allen head socket and an O Ring..plus teflon tape if you want a little insurance... 11mm wrench or socket for the U joint and 10mm for the oil cooler block screws.. Hope this helps--It'll take you about 30 minutes if you have all tools handy. Not hard to do at all.