Hey guys new to the 4l sohc engines. How durable are they. Will they withstand the addition of a supercharger? How about occasional nitrous? Has anyone had any problems with chips or programmers? The vehicle is financed and i don't want to be re-financing just to pay for a new engine.

 

My dad had a 91 Explorer with a SOHC 4.0, it went 248,000 miles, then we sold it in perfect running condition! All I replaced was a fan clutch and lots of brake pads.

 

Did he swap engines, since the SOHC version didn't come out until '97?

Sorry 5x5, mine's an OHC, and I haven't put enough miles on it to compare anyways. From what I've read here, the first couple of years had some nagging problems with the timing chain tensioners. After that (or after repairing the afflicted years' motors, for those who had them) they seem to be a dependable motor though.

 

I remember in my mind the sohc stamped on the engine cover on the engine, but maybe Im wrong. No engine swap here for sure, though.

 

*edit* - Heck I even confused myself. Mine's an OHV, not OHC. -oops

 

I've got that engine in an 01 Ranger. It's been in twice for the "timing chain rattle" (they could never fix it), and had the rear main seal replaced, due to a slight leak. It has 57,xxx miles and runs strong, getting a consistent 16.5 mpg. How long will it last, who knows.

 

From what I've read you get abou 30K out of the tensioners on the SOHC before you gotta do it over again.

Who ever came up with OHV anyway. Valves on all engines are over the head. They are also in the head and below the head. They go through both sides of the head.

Really, it's either OHC or in block cam.

 

I don't know. Suppose they could aways bring back the flat-head V-8s. That's the only underhead-valve automobile motor I can think of.

 

My '02 Exploder has the 4.0L SOHC and 83,000 miles. Runs great, just like new. 21-22 mog on the open highway.

 

Recently traded the wife's 2002 with the 4.0L V-6 in for a 2005 4.6L V-8 under the "family and friends plan" . Did so because the 4.0 developed the imfamous timing chain tensioner problem at around 40,000 miles. From what I read it is a real hit or miss whether it can be truely fixed. I had an used oil analysis done and the showed much higher iron from the timing chain slapping around. Plus the chance of broken plastic parts jamming the oil pump and plugging the oil return ports was too great. And yes it did develop the classic chain rattle when the engine was "cold" and lasted until the the engine was truly warmed up. The noise occured in the 2400-3000 rpm range. Considering the price of the repair and the deal on the 2005 V-8 it was well worth getting the 2005. The 2002 looked great and ran perfect otherwise. They gave us $12,000 on it for trade in. Sales price of this Eddie Bauer loaded V-8 with the "family & friends plan" was less than the bare bones 2002 XLT V-6 at $200 above invoice cost at the time. And as a bonus the V-8 is getting the same mpg as the V-6 and it's not even broke in yet. It was a win win situation to trade it.

Whimsey

 

Do 4.0 always last that long when they are taken care of?

 

I think the "SOHC" and "OHV" acronyms describe the location of the camshaft in relation to the heads. On an OHV, the heads (valves) are over the cam. On a SOHC, the cam is over the (heads) valves.

It is a little confusing though, no matter how you look at it.

 

That get's pretty technically deceiving doen't it? But not technically true. The valves are still in the head, over the head and when actuated, below the head. I guess it should be called OCV - over cam valve.

 

I have a 99 XLT with the SOHC, I get the rattle at start-up but then it seems to go away, the dealer did the chain tensioners and it did nothing for the noise. I have 153,000 miles on it and it runs perfect, burns no oil, so my theory is if it ain't broke don't fix it.

 

My sister's explorer had 455,000 kms until last thursday when 2 moose tried to give it a kiss at 65 mph