So I took my 2001 ranger 3.0 xlt to the shop, and they're telling me it has bad compression on cylinder 6. They say I have to replace the entire engine, and that there is no other way to fix it. Is that true?

 

Welcome to the forum

Depends on your symptoms

In general if you just had a misfire(code P0306), and no other noise like a loud "knocking", then most likely cause of low compression in one or more cylinders is a bad exhaust valve
That can be repaired by rebuilding or replacing the heads on both sides, and that can be done with engine in the vehicle

If your engine has more than 350k miles then it might not be a bad idea for a full rebuild, i.e. replacement engine, usually 400k is about the time for full rebuild in any case

A shop needs to warranty its work, if they just quote you new heads and once they got the old heads off, they saw that there were piston/cylinder issues then they would have to tell you you need a full rebuild/replacement engine at that time and they had already invested 8 hours to do the tear down

So if they quote you on a new replacement engine they are covered, no guessing that the pistons and cylinders are OK


I know its ridicules, but..........if you have a dirty ashtray in your vehicle , and I quote you to replace the WHOLE vehicle to get you a clean ashtray am I wrong?
Would the new vehicle have a clean ashtray or not?
If it does have a clean ashtray, then my quote was correct to solve the problem of the dirty ashtray, ridicules, but TOTALLY correct

Shops have to work within parameters of worse case scenario, replacing the whole engine WOULD solve the problem of low compression in #6
Replacing just the heads COULD solve the problem of low compression in #6, 95% of the time
Its that 5% that can come back to bite the Shop in the butt, because customer will think they are "ripoffs" by quoting a head swap and then changing to a whole engine swap, that's at least twice the price, and doing it half way through the job to boot

So do you need a whole engine swap, I would say probably not just new heads
So having another Shop take a look wouldn't hurt, at least one that would give you the option if they think it may be just a burnt valve, there are tests for that, a dry and wet compression test
A Bore scope can be used down spark plug holes to see piston and cylinder wall condition

 

Alright, thank you for your input. My truck only has 160000 miles. No knocking sound, but hesitation and shuddering and shaking, no pick-up. The code I got was p0306, and the compression test said cylinder 6 was bad. So what exactly should I order as far as parts go? I can do the work myself, pretty sure. I'm definitely not gonna pay that shop $3500 for a 110,000 mile engine, just to have them resell my current engine. No way. So please, if you have time, explain EXACTLY what I need to purchase and I can use YouTube to figure out how to do the repair. Thank you

 

You will need 2001 Ford Ranger 3.0l head gasket "set/kit", it comes with the 2 heads gaskets, but also all the other new gaskets needed to reassemble the engine
(must be for Ford Ranger, NOT Ford Taurus 3.0l head gaskets)
A new set of head bolts, old ones can't be reused, for 2001 3.0l, (1991-1998 head bolts won't work)
A new thermostat, 190-195degF

New oil and oil filter, do not drain oil until new heads are on, cleaning up the block after heads are off will cause debris to go into oil pan, so wait to drain the oil and all that stuff will come out with the old oil

New coolant, but I would refill cooling system with water, and run that for a few days to make sure there are no leaks, then drain and refill with new coolant

RTV sealant

New heads with valves are expensive($350 each), make sure heads you are looking at are "complete", less expensive heads are usually just the heads with no valves
Call local machine shops and see what their price is for doing a valve job on both heads, that will include pressure testing and surfacing, and approx. time it will take, usually 3 to 4 "business" days
Then you have a comparison price vs new heads, you do have to ship your heads back, that's often included in the price of the new heads but check to make sure
Benefit of new heads is quick turn around time, because new heads can be on hand before you remove old heads, no 3 or 4 day delay so difference in price is the delay

You need a set of hand tools with metric sockets
A torque wrench for reassembly
Wire brush and scraper to clean block surfaces and piston tops
Take lots of picture of wiring and hoses as you disassemble the top of engine, it will help on reassembly

One thing I do when I will be pulling heads on a running vehicle, I have a local exhaust shop that I pay cash to for them to loosen the exhaust manifold bolts and replace any that break or get rounded off, most I ever paid was $80 and they have to replace every bolt on the 4.0l exhaust manifolds, and took them almost 2 hours, would have taken me 2 days, most likely, lol, usually its under $50
Also loosen EGR tube at both ends
They do this work daily and have all the tools needed to get out stuck or broken off exhaust bolts

 

...also check the casting numbers on your old heads to compare with new head numbers before ordering if you go that route, and make sure they are compatible.