Every engine is different i have seen ones last 400,000 and ones that last 50,000. You need to listen makes sure it not making any weird noises. See how the oil looks. Look inside the oil cap and see if you see anything abnormal. Check the coolant and see how that looks. My 98 Lasted 150,000 and got the engine replaced. The 94 i bought in 04 with 130,000 and now it has 250,000.

there was a recall on the vortecs for the peice of crap injection setup and now that the trucks are old you are stuck paying the 300 for it by yourself. the pumps suck and for me its 200 for sending unit. intake manifold gaskets are plastic junk and when you do it you have to take it to someone to have the cam retard offset(timing) set with a expensive scanner. theres 4 o2'* to deal with. the caps and rotors are more expensive and dont seem to last.they are picky about the parts you put in and dont run right unless good stuff is used.
the 4l60 isnt much better than the 700r4. the steering boxes wear prematurely compared to other trucks as well as the idler and pitman arm. at least you will have normal fuel lines, ive got weird hard to find stuff.

It depends on the truck some only have 3 like my 98 and some have the 4. If you do reseal the intake if you mark the distributor before you take it out you dont have to worry about getting it cam retard set. The injector assembly wasnt a recall it was a tsb for cleaning the popetts. The only thing i have seen the engines being picky about is the plugs i will never use anything but acdelco in mine because of that. My 94 has the 4l60 and thats been through the ringer plenty and still going strong.

well it appears to need a head gasket replaced so while im in there ill do intake manifold gaskets as well. and along with weird noises...i took in for a test drive, from starting it cold, and it made a weird wining noise that came through the center area of the dash, kind of where the radio is and such. our mustang does the same thing but its the ignition and it comes in through the radio speakers...old mustang. but this wining noise didnt come through the speakers, i have no idea where it came from. after just a few minuts of driving it went away and didnt come back. what could this be? it ran just fine with no issues when i drove it.

The noise could of been the belt. If and when you do the hed gaskets make double sure you set the valve lash correct or it will cause problems the vortec are picking. I had two clyinders off just a little and cause missfires.

it could have been the belt, but it wasnt that kind of noise. and the belt didnt make noise when i had the engine running and was checking everything out. could it be a bearing in one of the accesories or something much worse? it sounded more like a bearing noise, but im not positive.

It is possible it was one of the accesories or a idler pulley.

definetely look at the transmission and how well maintained everything is on the truck, a well maintained chevy 350 will last you forever

thats what i was leaning towards was just an accesory or something not to terrible. and yes i believe that, the chevy 350s are great engines, i wouldnt drive any other gas engine!! thanks for your help everyone, ill be sure to make a new thread if i have any further questions. thanks again!!

the vortec 350'* all have 4. i did mark it got it back perfect and still had to have it set it was off enough to start retarding the advance. doesnt matter what it officially was they where replacing the poppets with the electronic conversion ive read through the gm document but i cant find it now for some reason. regardless we get stuck paying for the peice of junk they fielded. the whole ignition, pump, fpr all has to be delco, nothing else seems to run right. and you must have the only 4l60 that works right, do a search.