Possible Spun Rod Bearing? W/ Video

[MalcolmV8]

Hmm it sure does sound similar to piston slap after watching those videos. I'm praying its not, it would be to bad to have to rebuild such a low mileage engine.

I did a little bit of searching around, and read about the whole "why you shouldn't do 5-6th gear pulls on these motors" its too bad, before buying I did some research and read about how stout these engines are with their stock forged internals.

Like I said before, it was after doing a 2nd to 4th gear pull when I noticed the noise.

If it does end up being a burnt piston or spun rod bearing, I want to make sure I do this rebuild right to avoid this again. I'm thinking bore .020 over, aftermarket oversize pistons with lower ring walls, stock rods if I can, and same with the crankshaft with a polish. I want to keep this my daily with some power nothing crazy though. Any suggestions with head work? Should I try to find some revised 05 heads or just mod mine?

Thanks again for the input fellas, the shop will let me know what happened tomorrow, I'll keep you guys posted!

If you do end up doing a rebuild just increase your piston to wall clearance per the piston manufacture's specs. Since that rebuild I've hammered my car from a stop or slow roll to top of 5th to 160+ multiple times, even on spray with no issues. The pistons now have some room to expand.

FYI - back when I had my issue and I wanted to check for a spun rod bearing I supported the motor with my engine hoist and dropped the k-member, pulled the oil pan and all the rod caps to inspect my rod bearings. All looked fine so I put it all back and yanked the motor.

Another thing that tipped me off was using a mechanics stethoscope. It seemed no matter where I put it, top, bottom, sides the noise sounded the same but then under the car around the transmission area I stuck it on the exhaust and pass side was noticeably louder than driver's side. At that point I knew I had a specific cylinder which of course it turned out to be.

FYI my number 4 piston when I pulled it out

The other side of it

 

[TRMN8RCRIS]

Bad news fellas, looks like I am going to have to do a rebuild after all, I called the shop today and asked if there was any update, they looked into the heads and found no damage meaning its a bottom end issue. They wanted a bunch of money to take the motor apart so I'm just going to bring it to my buddies shop and have them take it apart and look for the damage. I fly out to California tomorrow, so I'll just be telling my buddy from here on out what to do with the motor.

If its just a scored piston I plan on just reusing the rods and crank, upgrade to aftermarket pistons and bearings. Have them take it to a machine shop to increase the piston to wall clearance, and the basic machining for a rebuild.

As far as my heads go, I'm still not sure if it will be better to look for a revised 05 head or mod the heads I currently have.

Hopefully I can keep this all under $4k lol

Thanks again, I'll make sure to keep this updated and upload some pics of the damage.

*Edit* So I just found out about the reman engines, from what I read they are pretty stout, even more then stock. Would I just be better off with a reman then a rebuild?
I found this website that sells aer reman motors
http://www.handhautoparts.net/reman-engines-1/
Hopefully they have some in stock without a long a$$ wait!

 

[O.W. Kenobeno]

Reman would be a quick fix to your situation - with a warranty.

 

[Zemedici]

Reman would be a quick fix to your situation - with a warranty.

troof.

 

[03cobraaa]

Im currently going through a similar issue. My car was first diagnosed with a valve guide tick from Ford. After ripping the heads off, having them checked, cleaned, surfaced, and new seals installed it turns out my guides looked brand new. So now I am at the point where the motor is out getting the bottom end tore down to find any issues. My car did show it had excessive heat at one point. Also had shown areas on the piston where had been damaged from debris or slightly coming into contact with the head. One possibility was that considering my car only has 11k miles that the crank was dry on a start up causing the rod bearing to turn enough for the piston to slightly tap the head.

I had a very similar noise to what you are having. Unplugging injectors did not change the noise, and it didn't tap on a cold start or over 1k rpms. That's one reason I did not expect the rod bearing issue. So that is where I am currently. Ill update as I know more of what comes about them inspecting my bottom end. I also will be replacing the followers/lash adjusters just to be safe.

 

[Ourobos]

My suspected head tick was a lifted ring land on #7.. A new set of heads, some Diamond pistons, and about $2500 later I was good to go.

 

[MalcolmV8]

Unplugging injectors did not change the noise, and it didn't tap on a cold start or over 1k rpms. That's one reason I did not expect the rod bearing issue.

My scuffed piston noise I posted above made noise constantly. Right from cold start to warm driving and any RPM. Just for reference.

 

[03cobraaa]

If it helps any, just came home from the machine shop and mine snapped a wrist pin.