I popped the cap to check the radiator fluid and this is what I see. This was new coolant 1 year ago. Now it looks like mud. Scrapped it off and there is fluid under there....


Here's what I know:
- The truck is running rough
- It's not running hot
- It's not blowing any white smoke
- Radiator going through about a cup of coolant a week
- Just changed the oil and it was not milky

I'm thinking head gasket? Any thoughts?

Also, I see that Felpro makes a heavy duty perma torque gasket part # 519SD. Called Felpro and they recommend it since I pull a heavy boat. Anyone have experience with this gasket?

Thank you,
Mike

 

Two different types of coolant mixed in there, I bet. The entire system needs to be flushed ASAP. Run green colored, traditional coolant only.

 

To me it looks like Bars stop leak, but what ever it is flush the system then pressure test it before you take it apart, do a comp test as well.

 

that's FUGLY... ouch...

I once had a quick lube joint change my oil.. they topped off my washer fluid, which was nice of them.. they topped it off with coolant, as it turned out.. guess what they topped off my overflow with? .... now THAT was a mess.. congealed crap everywhere.. but it still wasn't THAT fugly..

I'm with Merc.. someone attempted to seal a headgasket is my figuring..

 

+1 on flushing. I had the same issue. Flush with cleaner a couple of times and run with plain water between. I drove 30 to 40 miles with cleaner and without each time.



I also checked for exhaust gasses in system before adding coolant.

 

I have owned the truck since new. I had a cracked head a year ago and replaced them both at the same time. Doing so I replaced the head gaskets and added new coolant. I added only green coolant after completely flushing the system over a period of a few weeks by swapping distilled water after each flush (3 times). No stop leak has been added.

While I agree on the flushing, which will need to occur anyway, That doesn't explain the decrease in coolant weekly.

I did a compression check in June and the numbers were all fine 160-170. This was before going on a long trip pulling a boat. Seemed to start running rough after that trip. A mechanic said based on the symptoms the head gasket might be blown between the cylinder and a coolant location. Possibly sucking coolant into a cylinder causing the pinging.

I'll do a compression check and compare to the previous numbers and let you know. Thanks for the input so far.

 

Check compression when the engine is really, really hot. I had a Jeep Wagoneer with a 401 that had that crud in the radiator. I did a compression test, a radiator draw-down test and a "smoke test" and it all showed no leak-but I tested everything from a cold engine. When I repeated all 3 tests while the engine was hot, all 3 test showed positive for a leak-a tiny tear in the head gasket that only leaked when the engine got very hot.

 

Or that may be rust build up from inside radiator if youve ever used straight water....but like others said it needs to be fluahed

 

x2 on the flush and the pressure test.

it does look like stop leak in the pic though. bought a van a while back and it had a bit of that stop leak crap in the radiator. looked just like that, just not as much lol

 

Interesting enough I replaced the heater core when I did the heads since it was starting to leak and the radiator was replaced about 18 months ago. I can tell you that after flushing the system 3 times with radiator flush and distilled water that is was clean as could be. I even checked the coolant before the trip mentioned above and it was green and full. Something changed after that trip pulling the boat for 4 hours.