Although I have never had the displeasure of throwing a rod while driving I have driven several vehicles with badly worn crankshafts that resulted in the connecting rods knocking. More than one was driven many miles with the oil light flickering and the engine threatening to break loose at any moment but all made it to the shop. It is difficult to imagine how an engine could self destruct so completely without a great deal of warning. All the thrown rods that I have seen occurred with the engines apparently at or near wide open throttle and red line. Engines grossly over filled with oil have arrived with a trail of smoke from the exhaust and from under the hood with dip sticks pushed out, oil leaking from seals and gaskets and being dumped into the air filter housing. The drivers were having a difficult time keeping the engines running. None that arrived over filled required more than cleaning up and sealing and new spark plugs. But, as previously stated, a 3.9 Mopar has never arrived over filled.
Well, It seems oldschool has taken this thread off on a tangent. So lets get back on track.
Yes, oldschool, my wife is guilty of not checking the oil level when she had the “professional” service done. As you elude to, It is really a sad statement that every driver has to be a mechanic. Prior to this event, I would also have be guilty of not checking the level. As I got older, laying on cold cement to change oil in my garage was becoming more and more painful. Sorry to say, I am now changing my own oil again… since pain goes away… but a blown engine doesn’t.
Anyway, I personally replaced the engine in the Dakota. Upon disassembly of the damaged engine, I found the rod broke and bent in several places around the narrow metal sections that retain the bearing. The piston and linear portion of the rod were still hanging out of the (now damage) cylinder bore. The lower rod piece I salvaged from the pan is severely grooved, so there is little doubt the bearing was spinning. I am not sure what piece did the block/pan damage.
For those asking about mileage, the engine only had 89,000 on it after ten years. Low mileage by today’s standard. The oil I drained out was as black as used oil, so I suspect they loaded the new oil on top of the old. I do give them credit for (at least) changing the oil filter.
Anyway, the lawsuit has been filed in small claims court. Let’s see what happens.
Was the cylinder broken through to the water jacket? If so that would possibly be the cause for the dipstick indicating over filling. We each must attempt to deduce the situation based on the information given and our own experience and when engines with hydraulic lifters such as the 3.9 Mopar are excessively overfilled the oil will certainly froth and before the bearings are damaged the lifters will collapse and the engine will lose power and become quite noisy. If the driver is aggravated at the loss of power and stands on the gas in a determined effort to accelerate with no concern for the consequences a thrown rod is certainly possible. My best guess is that whether there was an over fill condition or not the engine was making some high revs and beginning to make some unhealthy sounds when it began to self destruct.
When I worked at a Dodge dealer I noticed that most 3.9 liter engines were over filled. The grease monkeys working there were unaware these engine only hold 4 quarts of oil. I didn’t see any broke pistons or connecting rods because of this.
A four quart oil capacity in a truck engine was a really bad idea, less durable when it comes to neglect. So many people try to go 10,000 miles between oil changes. They bring thier sludged up engines in for an oil change, the clean oil washes the sludge down to the oil pan and 175 miles later their oil pump is plugged.
This just happen to me in 2009 tahoe . Went to get oil change 30 mins later truck started shaking check engine light came on oil pressure dropped call shop told them what was going on they ask to get it towed our cam I make it to to next locations shop .went to other shop was was told it was 3 quarts to much oil in my Tahoe and it threw a code mis fire in 4 … other shop tried to figure how to fix the problem but nothing work was then told my problem is in my engine. So other shop called me and said I must have added the oil that they only put 6 quarts in . So I said why would I put oil in my truck when I just got a oil change . So filed claim with there insurance frist thing the guy tell me was the shop said I add oil to my truck I said no how does that sound. Now still waiting on adjuster to come look at my vehicle.
Sometimes a shop will inadvertently add something to the crankcase when they are actually trying to add it to the transmission or cooling system. Suggest to check for low fluid levels elsewhere, like the coolant, or the transmission. The suggestion that you added the oil 30 minutes after you just got an oil change is ludicrous. They are probably just trying to cover their tracks, as this may result in an expensive repair. If you continue to run into road blocks suggest to post this here, but as a new topic.
Ya suppose after ten years, the matter has been settled?
SSL’s post above within past 24 hours.