my truck is knocking.....

[stuntin andy]

it has been wweeelll taken care of... the last time we got the oil changed we took it to the shop because we had no time and they put synthetic in it.... well needless to say my truck dident like it it was eating the oil... so today we switched it with the normal 10w 40 and now its knocking... wtf?!?! like i went for a cruse for maby 40min?!?! and now its knocking whats the deal yall?

[Kickstarts-suck]

What kind of truck and engine? Mileage?

[yellowzo3]

If its a chevy, ('99-'06 or whatever that body style is) knocking on start up is "normal" and a TON of trucks have that problem. Ours has always done it and there's really not much you can do.

However, we run 5w30, non synthetic.

[CJM]

Startup knock is piston slap, ford 5.4L does it and some chevys. It usually goes away after a min or so.

If its constant then you got problems and will need an engine/rebuild.

[sexysilverado45]

What motor 4.8,5.3.or 6.0.Is it throwing any codes. Does it run any different like dogging.

[chucked]

Startup knocking is almost always lifters. They need a few seconds to be charged with oil pressure.

[stuntin andy]

its a 5.0 efi and it has never dont it before... it has like 153k miles.. but the thing is that i was going to go look at it this morning and now its not knocking..

and its not when it starts it was after i was driving it for like 40min....

[F-16Guy]

Spun bearing? Could just be coincidence, or maybe it was about to go and the synthetic let it slide easier. Hard to tell without being there to listen to it. Could also be a lifter not pumping up. Could be a million things....

[stuntin andy]

hmm i think im going to go dirve it again and see if it acts dumb

your not supposed to switch to synthetic after a long period of time as it will usually create more problems. if its not diesel what about running the highest pump gas?

[Kickstarts-suck]

Originally posted by FlewByU352
if its not diesel what about running the highest pump gas?

Its a old 5.0. They run on 70 octane. :p

Alot of people say its just fine to go to synthetic with alot of miles and then some say don't.

I personally wouldn't.

What weight oil are you using? Check oil pressure.

Originally posted by Kickstarts-suck
Its a old 5.0. They run on 70 octane. :p

lmao in that case even the lowest gas in Mexico will do.

[250x_kyle]

check oil pressure. possibly a sticking lifter. but like someone else said is it throwing any codes?

[chucked]

If it was me the first thing i would do is cut the oil filter open and check for metal. They say not to switch back because synthetic oil swells the seals then when you go back it will leak.

[sexysilverado45]

Chevy doesn't make a 5.0 in those years. I think your worried about nothing. Both of my 5.3 had a slight tick to them its normal. The sound at the begging is piston slap.

Is the noise louder than piston slap?

[chucked]

I dont see where he said a year

[Drewltr450]

Stay running conventional and try lucas oil stabalizer i notice a WORLD of difference when i run it in my cars,bikes,motors etc... Lucas works wonders. Also seafoam the whole motor. Put in in the engine oil, gas ,down the intake everything. Bet your problems will go away.

[stuntin andy]

my dads buddy said it is the oil screen .... so im going to rip the oil pan off and change the screen and oil pump then im giving it to my dad ans im taking his lifted jeep off his hands >=)

[chucked]

Wow

[stuntin andy]

lol good deal ehh?

[chucked]

No, i like how he took a blind shot in the dark at what could be wrong.

[Kickstarts-suck]

Originally posted by chucked
No, i like how he took a blind shot in the dark at what could be wrong.

Exactly :huh

[CJM]

Oil screen? Nope that aint it. Thats a real shot in the dark...

Again what kinda truck is it? 5.0 can be ford or chevy (yes they made them with a 305 aka 5.0 till late 99).

Either way betcha 10 bucks if it happens after driving for awhile the bearings in the bottom end are bad. HOWEVER as a good example, just cause they are bad doesnt mean the trucks totally a loss. One of the work vans I have has had a bottom end knock for eons, 80k miles since we got it and the engine runs fine believe it or not.

[stuntin andy]

idk yall it kinda makes sence.. think about it... the oil is getting clogged in the screen so the oil pump cant pick up the oil and give it to the lifters.. so it has no oil pressure and that should make it knock... =o i think lol..... its a 94 f150 5.0efi awd xlt lol

[CJM]

Ok so its a 302.. it is 4wd not awd either btw, awd is not 4wd.

I doubt the oil screen is the issue, it has tons of miles, you swapped to syn, the bearings in the bottomend go on those motors sometimes.

Want to see if its getting oil, pull the topend apart and look at the cam for scrape marks, if it has some its not getting enough oil. Otherwise bottomend most likely.

I had a 302 blow on me due to the drivers (company truck) forgetting to add oil as it had tons of miles. It ran like that on 6cyls for a bit, but the knock was deff in the bottom. Sounded like someone was taking a hammer and hitting metal in that spot.