2011 Ford Ranger Sport, 4.0 with 105,000 miles started running rough coming down exit ramp. Felt like brakes were failing while engine was knocking. Stopped immediately and checked all fluids (as just had an oil change and fluids topped last week). Everything under hood looked fine (but still noise). This was first trip out after oil change. We drove about 100 miles today with no issues. Engine still knocking and drove 5 more miles to auto parts store to have them run codes. Code P0301 (cylinder 1 misfire) and P0420 (catalyst system efficiency below threshold). Auto parts store thought we just needed spark plug. Drove the remaining 3 miles home when all kinds of noises and truck engine quit (battery light came on at that time). Presently, engine will not turn over. HELP!

 

Knocking and very noisy is not a good sign. But hey, the part store guy thinks you just need plugs.....When you say you checked the fluids, What did you look for? Have a look at the oil again wipe it on a clean rag.

 

Thanks. Now that you mention it, the oil did seem dark tohave just had an oil change. Will check it in the AM.

 

Reads like you spun a rod or main bearing, so yes, engine rebuild or replace
Remove all 6 spark plugs and try starter motor again
Also try turning crank by hand using pulley bolt
Should spin easily with no compression in all cylinders

If not then a bearing has melted and welded itself to it's journal, so engine must be pulled



Power brakes need engine vacuum to work, rough running engine usually has LOW Vacuum, which why the brakes were acting up

Battery light comes on with Key on engine off, so if engine stops with key on battery light comes on

 

It appears that the shop overfilled the oil during the oil change. With the engine cold (since it
had not run since engine failure yesterday) the oil on the dipstick was double the maximum amount. For example, if maximum was 2” then oil on dipstick was 4”.
The truck was only driven 89 miles round trip total after oil change prior to engine failure. All miles were put on the same day (yesterday) with a 4 hour rest in between the 44.5 miles each way.
Truck was towed to a different shop for evaluation.
All comments greatly appreciated!

 

That could definitely cause an issue

 

So this is what the mechanic said:

“Ok so bad news is the engine is shot. It is not overfilled with engine oil. The oil pan is filled with coolant. The radiator is low. I drained about 6-7 quarts of antifreeze out till I got to oil. Then the dipstick shows full.
My thoughts are just coincidental
But could have been run hot or head or head gaskets failed and flooded the crankcase

The oil pump sucked the coolant and seized the bearings”

we are meeting him in the morning. What questions should we ask? The truck temp never ran hot. Needle was at half way as it always is.

 

Not much you can ask, unless the oil change guys put in coolant instead of oil it is just a coincidence
I assume the oil change guys never told you "hey did you know there is coolant in your old oil?"
But they may not have looked at the old oil, just drain it and replaced the filter without looking

But if coolant level was low in radiator then cooling system is most likely where the coolant came from not from a mistake at oil change place

Won't run hot until coolant level gets fairly low, bearings will usually seize first, especially if it was driven several times with coolant in the oil
The bearings heat up instantly, within 1 minute, the engine as a whole takes 10-15 minutes before you would notice it over heating on the gauge

Oil is used to lube and to cool the bearings because it has a high vapor point, 400degF
Coolant/water on the other hand has a low vapor point, 230degF
Bearings run 230+ degF
So what happens is the coolant in the oil flashes to "steam" on contact with hot bearing surfaces and washes off ALL the oil.............so bearing gets even hotter
Bearing eventually melts and welds itself in place seizing the engine

 

Thanks RonD. The oil change shop topped off all fluids when they changed the oil. They apparently meter oil out of a drum. Don’t know where they put or look at the oil that they drain.
The truck was driven ~2 miles home from shop on Friday, then driven about 2 miles Saturday to the trash dump and back. The truck wasn’t driven at all Sunday. Monday truck was driven to a job site about 40 miles (one way). It sat for a little over 4 hours before we drove back home. Engine gauge never moved past its half way mark (where it normally runs).
Just trying to understand why this engine which has been well maintained would fail with only 105,000 miles on it. Seems a little premature. Any insight?

 

Coolant was in the oil.........................miles do not matter when that happens

If you want to find out WHY coolant was in the oil then you would need to disassemble the engine and look for "the smoking gun"