So last fall I was driving my Ranger home, and started to notice a light knock. I definitely should have stopped right away, but I didn't of course and by the time I got home it had gotten worse. Checked the oil and there was none on the stick! Oil pressure gage hadn't been working for a while, which I clearly should have gotten fixed in the beginning. It's now been sitting for months and I'm still trying to figure out what to do with it.

I will have to figure out what caused the loss of oil, since it rarely used oil and had only been 2k since last change. But I'm more concerned with what may have happened to the motor. My initial thought was to just buy a new motor, since mine has 265k on it, but I am wondering if mine may be cheaper to fix than just buying a replacement. I am not overly experienced in working on cars myself, but I'm now able to use this truck as a learning vehicle since it's not my daily.

Basically, what I'm asking is, any thoughts on what to look for in what could be causing the terrible knock? Everything I've read and heard is likely the main rod bearings, but how would I diagnose this? And if this is the issue, would that be worth fixing?

Thanks,

Eric

Plastigauge is used to check bearing clearances. There is no such thing as "main rod bearings", there are rod bearing and there are main bearings.

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2004 Ranger FX4 Level II, 5R55E, Sonic Blue Pearl

Proudly JAP/RICE free since March 2000

These Duratecs have a known issues for the valve cover to leak between cylinder 2 & 3 right where the Coolant Temp Sensor is. The oil fills up in the spark plug holes. Mine leaks down the passenger side towards the back and burns off the exhaust manifold.

I lose about 2 quarts every 6 months I think. Got a nice little scare when I was in Pismo Beach and the oil light popped on for a second, killed it quick and rolled into a gas station and put 2.5 quarts in.

That was in July 2016, and then a couple days ago I put another 2 quarts in.

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2007 Regular Cab - 2.3 DOHC - 5 Speed Auto - 4.10 Gears - Maxtrac 7" Lift - Fiberwerx 3" Fenders - Bilstein 5100 Series - 15x10 Ultra 164's - 35x12.50x15 Red Letters - Custom dents

I would agree with checking the valve cover gasket mine had a leak there up until it got a bad wrist pin/piston ring. There is a way to check the rod bearings basically what you do is drop the oil pan and wiggle the bearings up and down if one moves there's your culprit. Do you know what cylinder is knocking?

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04 Ranger single cab reg bed 2.3l Duratec row your own gears(manual transmission)

I have not pin pointed which cylinder is knocking, I will see if I can figure that out. But I will definitely check the valve cover gasket and see if that may have been the culprit for the leak itself. My concern, however, is that it's too late even if that is the case. I'll check the gasket first and make sure the oil is at the max and see what happens. If that doesn't help, I'll probably go the route of dropping the pan and see if I notice and movement in any of the bearings. Like I said, it will be a learning experience if nothing else.

Thanks

As Bill said, you can use plastiguage to check bearing clearances. I always used it on initial build, haven't used it as a diagnostic, but I don't see why it wouldn't work. With 265k on the clock, I question whether it is worth it to fix this one issue vs a total rebuild. A little 4 like that wold be pretty easy, I am thinking you could do it in a weekend.

Yeah maybe I should just start to look at a full rebuild. My concern would be if the crank was damaged at all I'd have to get it machined at least correct? Not sure how much that would cost at a machine shop, but I could look into that.

I may also just start looking for a replacement motor for a swap. But a rebuild may be fun too.

I haven't gone shopping for a longggggg time but there used to be crank kits available. They came with a turned crank, rod and min inserts, gaskets + seals and possibly an oil pump. If you really want to be tight with the $, then after inspection to see what failed it is possible that the no-oil event took out just an insert and not the crank. As for putting a rebuilt engine in the vehicle, most people look at the overall condition of the vehicle as a whole and determine if that's a smart move. Sometimes, for some vehicles, fixing the problem or a used engine makes sense.

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2004 Ranger FX4 Level II, 5R55E, Sonic Blue Pearl

Proudly JAP/RICE free since March 2000

It is possible that the bearing insert was damaged, but has not caused the rod journal to be too damaged to live with a replacement insert. Lifetime would likely be less than from factory originally, but it could last a long while with just some new inserts.
I would drop the oil pan, see if one rod was looser than the others, and if so, remove that rod cap and inspect the insert and the bearing journal. Look also at the top half of the insert, as it gets more pressure than the bottom half.
You could just get a set of standard size inserts, install them all, and put it back together and hope. If you kept it full of oil, and kept the rpms down from zoom zoom zoom, it could last until you had more time to consider alternatives.
A used engine could be the correct choice, if available at reasonable cost, and the condition of you truck doesn't warrant a $2-2.5k rebuilt. Second alternative is to drop the crankshaft out the bottom, have it machined and then install with new under-size inserts. Put the front cover, flywheel, and pulleys on, add the pan, and drive away... Again, can be done w/o a crane/cherry picker, but you'll need some muscle or floor jacks to raise the crank back into place so the main bearing caps & inserts can be installed.
Do some math, check some boneyards, check car - part dot com for replacement used, check auto parts stores & machine shops for crankshaft work & inserts & gaskets.
tom

It's been like 10 years, but the crank kits I was looking at was the crank and bearings, and if you stepped up you could get rods maybe pistons. But they didn't have a crank for my Suzuki, and an oil pump failure taking our a rod bearing did it dirt. But I found a shop that built the journal back up and re-ground it. Cool process.

Thanks for all the info! I do have access to a cherry picker actually so I'll probably try to pull it and put it on a stand. Then I'll be able to pull the pan and get a good look inside and go from there. I may be back with more questions depending on what I find.

Thanks again!

Flame spray/chrome plate and machine the part back to stock size. Same thing we'd call for when a jet engine mount had damage, repair is so much less costly than a new part.

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2004 Ranger FX4 Level II, 5R55E, Sonic Blue Pearl

Proudly JAP/RICE free since March 2000

If you decide to do a motor swap I would look into doing a 2.5l mzr/duratec swap you can find them for 100k miles less for 300 less big ones. I can give you the info I found while researching for the swap and also if your interested I would look into the Miata forums(nc Miata used a 2.0mzr and 2.3/2.5 swaps are pretty common over there). There's also a guy on YouTube that swapped in a 2.5 duratec into his/her ranger that may be able to give you info on how he done it.

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With these motors I would find it hard to do anything bottom end without a cherry picker or lift to pick up the motor at least a little bit the front of the oil pan rests on the crossmember that holds the front suspension. If you could elaborate a lil more on how to do that without a cherry picker or lift that would be amazing. I was looking into checking mine when I thought it was a rod bearing knocking and decided not to when I realized that I had to pick the motor up

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04 Ranger single cab reg bed 2.3l Duratec row your own gears(manual transmission)

That is definitely something I'll look into when if it comes to that. I'd definitely be interested in the information that you found on this swap. Do you know how much modification it would take to get it to fit? And also, do you know if it would match up to the transmission? The ranger is a 5 speed and the clutch still feels good, so it would be nice to be able to keep that in place.

Although now thinking about that, my daily driver is a mazdaspeed3 with the 2.3 DISI MZR, and that is fun engine! Likely that would require the 6 speed that comes with it, but that sounds like a fun truck! The body is in good enough shape that this might be fun too! Don't know what it'd take since that's only made in a fwd (in the speed3) and awd (in the speed6). Although I may be dreaming at this point, because that would definitely require a new harness, brakes, and tires since I'd be smoking them the whole time anyway.

No I don't know the amount of modification to make it fit but I know that the hardest part most people have with it is dealing with the vvt that's on it from what I have read is you can do a delete and just use your non vvt valve cover(ie the one on your truck now) also you should use your harness for it and swap over all necessary plugs. Most specifically if you get one from a Mazda. Also with the Mazda you will definitely want to swap the camshaft position sensor. Your transmission will mount straight up to the motor just use the rangers flywheel starter and clutch assembly. From what I have read about the disi swap over in the miata forums is that they were having a problem with the fuel return and high pressure fuel pump(some of the same issues with running a 2.0 ecoboost pre-2015 with a stand alone which fwi all the way up to 2015 all 4cyl ecoboost motors shared the same block as the duratec's)

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04 Ranger single cab reg bed 2.3l Duratec row your own gears(manual transmission)