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Mustang V-6 lifter or valve noise?

I have a 2011 Mustang base with the V-6 engine and 6 speed transmission. It is my summer car, getting fewer than 3,000 miles on it per year. I take very good care of it. My question is what is the mechanical knocking noise I am hearing on cold starts? It continues for about 5 minutes until the engine is fully warm, then stops. The noise comes from the valve cover area. It clearly is a noise that cycles with the movement of internal parts. I have no idea if it is normal or could be something serious. The car only has 10,000 miles on it (it was sold in 2010 as a 2011 model, so it is 5 years old now.

Well given the miles you put on it could be normal. Do you use a dealer for oil changes? just curious as an oil backflow preventer may be absent in the filter. I usually do not care one way or another about synthetic oil but it might be a good idea for you. of course without any hands on to hear the source it is a guessing game, could be a tensioner for all anyone knows.

Consult TSB 12-1-17.
Cam bucket noise on cold start on early build engines. TSB requires installation of cam oil restrictors and modification of camshaft retainers to increase oil flow to mechanical buckets/tappets. Approximately 2-3 hours of work, Not to bad.

You could have a sticky lifter and until it’s warmed and expanded a bit, it has a tendency to stick.

You could try adding a quart of ATF to the oil a few days before your next oil change. The ATF has more detergents than motor oil and it could help clear out any sediment that is binding up the lifters. The ATF won’t hurt the engine a bit, and I do this once a year with my truck.
I try to plan it that I put on 100 to 200 miles with the ATF added before the oil change.

Yosemite

jgre142e… Could you expand on your thoughts please? TSB? Service bulletin? Early build engines, does this apply to mine? What exactly is cam bucket noise? Camshaft something or another I assume. Are you saying Ford is aware of this problem and has the fix available? I assume it isn’t a recall, only a recommendation. Any more insight would be appreciated.

As for the other question, I do use the dealer for my once-a-year oil change due to low miles driven.

Is this the 4.0L SOHC V6? They are also prone to timing chain guide breakage. But, the valve cover would need to be removed to determine if that is the source.

No, it is the 3.7 I believe.

I found the TSB 12-1-17 on Google. Is this a good idea to have done or is it only a minor issue?

jr4488,

The 2011 6 cylinder engines are the 3.7L TiVCT… This engine uses mechanical buckets (DAMB-Direct Acting Mechanical Buckets) as opposed to hydraulic lifter/automatic lash adjustment configuration. This simply means that the camshaft pushes against a solid tappet to actuate the valves. Valve lash/clearance is fixed and can only be adjusted by replacing the bucket with a different length assemblies (Bucket)

The basic physics of the noise…Valve lash is the clearance between the cam lobe and the valve bucket. Tight valve lash tends to be quiet, loose lash tends to be louder. In the 3.7 L the lash has to be large enough to compensate for component expansion/contraction due to heat as well as valve seat erosion as the engine wears. When heated the lash decreases, when cold the lash increases. remember larger lash tends to be louder.

To reduce this clatter, oil is directed to the cam lobe and bucket interface which acts as a cushion/muffler to the cam to bucket event. The left cylinder head is the farthest point from the oil pump, so when cold, the oil flow to this area is reduced slightly. (Due to oil viscosity and other engine clearances) This situation results in less oil dampening of the valve buckets and consequently the clatter noise you are experiencing.

The issue you are having was a known issue when the 3.7L was first released in the Mustang. The Technical Service Bulletin provides the build date info related to which engines were known to have this issue. You can see if this applies to your vehicle by checking to see if the vehicle was built on or before 05/01/2011. (Build date can be found on drivers door sticker)

Don’t freak out, the noise is not detrimental to the life of the engine if the noise can is related to this TSB. Nothing is broke or being starved for lubrication. You can address it in the case it drives you crazy. The repair/TSB forces more oil to the noise locations. The engineers simply are flooding the bucket interfaces with oil to drown out the noise. The later build engines are build from the factory with the orifice plugs and modified cam TSB.

Check your vehicle build data please.

Isn’t the Powertrain Warranty 5 years/50k miles on this car or something like that?

This problem is a powertrain issue and even if it was nitpicked as not being covered you should ask FOMOCO (not the dealer) to step in with a Good Will warranty as a pre-approval.
Considering purchased from new and very few miles I would find it disgusting if Ford did not cover this for you free of charge.

Good comments above. Also, make sure to check the oil level on the dipstick. You might just be a little low. Having the valve clearances measured might be a good idea at this point too. 15K miles isn’t usually the interval for measuring valve clearances – on my Corolla it is 30 K or 60 K as I recall – but in your case it’s probably a good idea to measure them. That’s usually not a very difficult job for a shop. Fixing clearances out of spec is more difficult, but just measuring them isn’t.

I am back on this issue. Ford can fix it for $600 bucks. Is it worth it just for noise when cold?

Now there’s a long simmering issue. Do you want to spend $600 to try and fix issue? It’s ur car

I guess I need to know if the issue is hurting the engine…Ford says it is “a little”…but they also won’t recall the issue, just a TSB 12-1-17.