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What’s the best course of action for my 1987 GMC S15?


Topic starter

Scotty I have A 1987 GMC S15,Now but I had A 1986 GMC S15 also and they both broke .By burning A hole in the number one cylinder.It has A 2.5l engine. Are they A bad engine,if so what could I put In my truck? Thanks Mark

5 Answers

They are not a bad engine but you can burn a hole in any piston with an overly lean air fuel mixture.  If a carburetor isn't jetted properly or a fuel injection system isn't functioning, this can happen.  I'd get a reman motor with a warranty and start over, making sure everything is right.


Ah, the famous "Iron Duke" engine.  Great motor, but I agree with @doc to get a remanufactured one (prolly run ya $1500-2000 + labor).  I wouldn't waste time with a junkyard engine because anything that old is going to have its own problems.

The good thing is that those old S10/S15's are sharing the square-body love from the C/K trucks and values are going up.  It will be worth your investment to get the motor done right.


OK, so basically you have a barn-find S15 with a blown engine.  The direct answer to your question is yes, it's worth fixing, but only if the bones are good.  That's not something you can figure out here, that's gonna require someone who knows what they are doing get it up on a lift and lay eyes on it.  A little rust is OK, but if the underside is rotten, just part it out and be done with it.

Assuming it all checks out, then you have to decide what you want it to be.  It's not going to be a hot rod, and it's not going to be a daily driver. You basically have 2 choices:

There are a lot of S10/15's out there doing work as light-duty utility trucks. Picking up the occasional bag of feed or something like that.  Not restored esthetically, but running and driving with no mechanical deficits.  Trucks in this category mostly sell in the $4500-$7000 range.  

Then a few of them are restored hobby trucks.  IMO, the S10/15's are great for this.  A fully restored, show-quality C/K10 is gonna go for multiple tens of thousands of dollars; out of reach for most regular guys.  But for $10-15K you can get an S10/15 that will get you appreciative looks at your local "cars and coffee."

For what it's worth, I still think it's a great motor.  They made  a lot of those little 4-bangers, and parts are still easy to get.  Right now, Jegs has crate motors listed at $2500.

I personally had an '87 S10 with the same motor (4-cylinder, manual transmission, short-cab/short-bed, vinyl interior, UPS brown paint) and loved it.  Rock solid, though I sold it off in 1998.  This many years later, its still a good engine, but seriously, it's not a daily driver anymore.

Topic starter

Scotty I have A 1987 GMC S15 pickup The engine quit at A intersection smoked so hard that I had A hard time seeing. Limped it home and put it away. Do you think that the engine is good enough to buy remanufactured engine and drop it in? Or does that engine have to many problems It has very little rust. Been stored for sixteen years. I love this truck, Any thoughts? Thank Mark

You were already given good advice 6 months ago. Did another engine blow up? Or has the truck been sitting since March 2022?

Topic starter

This is A 2.8L engine want to know if you think that it was A good engine in its time?

Thank You Very much love your show and allways watching.