i have an 89 f-150 with a 302 and a 5 speed manual tranny. for the past week, the tranny has started making a ckicking noise that varies with the rpm's. the higher the rpm's, the faster it clicks. it has the noise whether the clutch is engaged or not. the noise is loud enough to hear in the cab while driving with the windows up. anyone have any ideas what it could be? thanks a lot for any help!

 

If your description is accurate, it can't be the transmission. If it's speed varies with engine rpm, regardless of whether the clutch is in or out, then it has to be engine related (when you push the clutch pedal in, the transmission only spins as the rear wheels move, so it couldn't be making a clicking noise). Is it possible that you have developed an exhaust leak?

Take care,
-Chris

 

Donate54, if you hear the sound coming from the dash area then it could be the manifold leaking. I currently have that situation with my passenger side manifold and it sounds like a ticking sound. It is leaking at the top of the manifold near the back of the engine. Think of the valves opening and closing when listening to it. My solution is to either buy another one (approx. $250-300 CDN each), take it off and get it plained OR just get a set of headers from Ford Racing ($545 CDN) which will increase my HP. Gee, that is my tough decision, NOT !! A set of headers by the springtime has been planned. If it is a manifold leaking, it would be a good time for a set of headers.

Have Fun & Keep on Truckin'
Dean

 

the speed of the noise does vary with rpm's (whether the clutch is engaged or not). i figured it was the tranny or maybe the clutch because when you climb under the truck, it sounds like its coming from where the tranny and engine meet. im gonna check for exhaust leaks tomorrow (im not gonna mess with it today, im just gonna eat turkey and be lazy ). could it also be a bad lifter or pushrod? also, my clutch is pretty worn down, could that cause it? after reading all you posts, im really starting to think that it could be an exhaust leak. ill post tomorrow after checking it out and tell you guys what i find. thanks for the input guys! happy thanksgiving...

edit: forgot to mention that i drove it around today and after a few minutes, the noise went away, then it came back louder, then it went away, then it came back not as loud, then got louder, etc... thanks for the help, i really appreciate it!

 

heres the update: i had a few mechanic friends of mine look at the truck and they all told me the same thing, its the lifters. when we opened the hood, you can definitely tell the noise is coming from the engine. is this something i need to get fixed right away? im in college so if i shouldnt use the truck like this, then looks like its time for public transportation until i can get enough money to fix it. what would cause the lifters to go bad? i have an 89 302, so im guessing that i have mechanical flat tappet lifters, right? is there any quick fix i can do? my dad told me not to let the engine rev up too high, and to use a thicker oil than what im using now (10w30). what do u guys think? thanks a lot!

 

If it were me, I would go by one quart of Slick 50 and 4 quarts of 20/50 oil and a filter, and change the oil. The Slick 50 may free up the lifters. Some people hate that stuff, but I swear by it.

Anyway, excuse my language, but it is now time to either ****t or get off the pot. What are you going to do as far as rebuilding? How much longer were you planning on waiting? If the Slick 50 doesn't clear up the lifters, then your father is right; drive gentle, and don't over-rev it. Your lifters are either gummed up, worn, or worn with a worn camshaft (btw, you have hydraulic lifters). I'm betting my money that it's a combination of being gummed up and both lifter and camshaft wear.

If the Slick 50 doesn't fix it, it's time to rebuild.

Take care,
-Chris

P.S. FYI, do you understand how I knew it was the engine and not the transmission? If not, ask me and I'll try to explain it better. Understanding how things work really helps with diagnostics, and I'm always happy to help someone learn.

 

let me see if i understand. you said it was the engine because it made the noise all the time and consistent with the rpm's, and if it were the tranny, it would have only made it while its moving (because the tranny only moves when the rear-end moves), right? the only thing that has held me this long from rebuilding the engine is the fact that i cant quite afford it yet. the cheapest quote i've gotten for a rebuild was $1200 (new pistons, rings, gaskets, bearings & oil pump). im gonna try the slick 50 out tomorrow. if it doesnt work, then im not gonna use the truck until i have the engine rebuilt (hopefully this winter as soon as this semester ends).

 

That sounds perfect. My only concern was if you were planning on having this engine rebuilt or if you were just going to buy a rebuilt. IIf you opt for the later, then you don't need to be terribly concerned with this one.

Take care,
-Chris

 

I'm just curious, how many miles do you have on the pick-up... this is only to satisfy my own curiosity...Thanks

 

completely stock 302, bought it with 65k miles and now its got 120k. only things i have changed on the engine are the timing belt and water pump.

 

Lifter tap is a common thing for 302 ford non roller cam.
Don't use slick fifty, you'll only add to the problem of gumming
up the lifters.My 93 used to it till I started using Mobil 1 oil
15W40.Oil weight has some to do with it, but the torque to yeild
rocker arms is a problem also.Every 302 I've owned has had lifter
tap.It's a flaw in the valve train and the oiling especially in pre 84
302s.I would invest in a good ground cam, lifters and timing chain.
I would go with a crate engine from Ford Motorsport.They have a complete swap for around $2500 and it is complete from the oil pan to the intake manifold(fuel injected) and is 285HP.

 

I had the same problem with my 1995 F-150 302. It was indeed the exaust manifold leaking. I was lucky, as all I had to do was torque the bolts down to specs amd all is well!! Good luck, Rick

 

In my experience, leaking manifolds will increase the clicking sound with load. My exhaust leaks were louder if I accelerated uphill, than when I rolled downhill. Lifter tap should not change that much with load. Leaking manifolds can also be detected by holding a metal rod to the manifold while the engine is running and then listening to the rod by using it as a stethoscope.

 

As I recall, Slick 50 solved it for him.

Take care,
-Chris

 

yes it did