Go to the amsoil web site and check out the article from lube&oil magazine.Amsoil is the only company that sells an extended drain interval synthetic that I know of and they stand behind it.I have used it since the early 80's and I can tell you the oil works.
www.amsoil.com

 

Oil gets dirty. Additives get depleted. I'll stick to 3k.

 

It was time for another oil change Sunday. I did notice the last 500 miles or so a slight tap when cold for maybe a second on the cold mornings. I added the Lucas Oil Stabilizer again, no more noise. FYI

Bryan

 

I have a '98 with a 4.6l. Bought it new. At about 75,000 miles it developed a cold knock (slap) which lasts about <30 secs. after startup, then disappears. Engine runs perfectly otherwise. It has been worse this cold northeast winter. I've been using 5W30 Castrol Syntec w/Fram filter since new. After reading the probs. here about Fram, and also hearing this from other sources, I changed to a Purolator filter this last oil change. I also put in 7 qts. of Mobil 1 0W20. Well it's only been a day, but there's absolutely no sign of the cold knock. It may be premature, but I'm hoping the combination M1 & Puro. has solved the problem.

 

Well, I also bought a 99 F250 last summer with 112k miles on it and have endured the "Piston Slap" issue. I also took it to the local Ford dealership. After 2 days they told me that their "master techs" told him everything was normal. They sent me on my merry way after relieving my overflowing wallet of the non-essential green paper that I just pull of the tree when I need more.

My concern is of the old school, noise means a problem, but, I ain't no tech. I tried changing the oil and going with the Motocraft antiflowback superduper oil filter. Engines stills sounds like a diesel starting up in the morning. Oh well, ...

Also have an 87 Chev, 3/4 with a 350 and 120k on it. Fires up and is as quiet as it was the day it was new. Go figure.... I have had offers to sell the Chev but I think I will hang on to it for a while. Been a good truck. Bought it new.


Take care guys, hope Ford will fix our problem but will not hold my breath on that wish.

 

My 1998 5.4 with 100000 Km also has engine knock but only when its colder than 0C (32F). The colder it gets the worst it gets. At -25C it lasts about 2-4 min then is gone. When I plug it in there is no knock at all. I'm using Mobil 1 5W30 and ford filtre. I was going to try 0W20 or 0W30 but have been waiting for some feed back if anyone else has tried oil before. JMETZ58 could you let us know how that 0W20 works out.

 

I'll keep the forum posted. The big question for me is what has (possibly) solved the problem, the filter, the oil, or both.

 

Jmetz58,

In my case, adding the Lucas Oil Stabilizer has seemed to quiet mine. I have used it for two oil changes now. I only started to notice the noise again in the last 500 or so miles before that most recent oil changes.

ottof,

From what I have heard, Ford has fixed the short piston skirt issue in the 2004's. If you read some of the replies, you still have a warranty, and you have a dealership that actually cares about the customer, they may replace the engine.

The way I look at it is this. We all made an investment of our hard earned $$$ when we bought these trucks. Buying a car, truck, or whatever vehicle is a poor investment. The value drops as soon as you sign that paperwork. If something breaks and it's not covered under warranty, fix it or sell it. If anyone can show me a PERFECT vehicle for under $25000, that will be my next purchase.

 

i bought my van a year and a half ago. i heard the noise. then read a post like this one. clean oil does seem too help. i have beaten on more than a few motors in my day some new some very old. piston slap is not that big a deal unless it is extream. Do i like it no i dont . do i think its gonna leave me on the side of the road no i dont. i am very happy with my van as a hole great milage good power.

 

my truck does it too...for about 30 seconds on a cold start you can hear the engine knocking a little bit...piston slap i guess...i run 5w30 Mobil 1 oil and a fram filter right now...think i will go to 5w20 oil and a motorcraft filter next...i have leaking headgaskets also so what do i know? warranty is fixing that though thank goodness...maybe i should try and get a new motor out of all this!

 

my truck has almost300000 kmws and just started to slap on cold mornings when oil is past 6000 km. mark after i change it its quietas a mouse. best truck and engine i ever had

 

Hi Guys, My 5.4 has the cold knock as well. It has about 75,000 Mi on it now. The difference is that I hear it until it comes up to normal operating tempature. +/- 5 minutes. I bought this used and have the balance of a 100,000 factory warranty. Should i go and fight for a new engine? It otherwise runs great. It is time to do plugs though, but that is another thread.

Thanks, Rayban

 

Hi
were you under factory warranty or you got lucky... I have the same problem!!! only at start up as soon as it is warm it will stop..
I would not mind loosing the truck for a month if I can get a new eng???
racer x

 

Were you under factory warranty??? how many miles did you have when this happened??
I have the same problem!!!! truly disappointed with this 5.4v8 Ford.

 

Its not a knock. Trying starting your truck with the AC turned off and see if it sill does it. I think its your AC compressor.