Is there an engine rattle issue on 4.0 SOHC

[krikf]

Have a '94 3.0, looking at buying a 2004 Ranger Edge 4.0 sohc automatic w/33,000 miles. Looks really good all over. Engine, trans, and rear end are clean as a whistle. Took a friend w/me for the final test drive today before buyng and he noticed (from the passenger seat) what he called a BAD knock or rattle above 3000 rpm any time I wound it out. I have some hearing loss and had not noticed it. We are both pretty good w/engines and I trust what he says he heard. Seems to come from the passenger side at the rear of the engine, or maybe the catalytic converter area there. He said it could even be a BAD spark knock. Again, it is only there when you really open it up.

I did not buy today. Would really appreciate your input here. The dealer really has this one priced right and it runs out REALLY nice other than this.

 

[Bent Bolt]

The 4.0l SOHC engine did have timing chain tensioner ( also called cassettes ) on the early models. About 2002 and newer are much more durable. When cassettes first start to fail, they typically rattle at start-up and at 1700-1800 rpms. As they progress, the engine will rattle all the time with a "loose chain" sound until the engine literally rattles itself to it's grave in a short time.

What you're describing sounds a lot like spark knock rather than cassette issues.


.

 

[snake]

I have had spark knock issues with my 4.0 (2002). Stealership replaced a few sensors, then finally reprogrammed the PCM under warranty. It still does it occasionally. The engines are supposedly notorious for blowing intake manifold gaskets which causes the problem (so I'm told).

 

[Jspafford]

I had the timing chain rattle when I had my 2001. It was noticeable at only certain times. Mine was mostly noisy from 2200-2800 RPM. It never made noise on startup IIRC.

I drove it for a while that way and then called the dealer. They offered no help, called Ford headquarters. They also told me to pound sand. I finally went to the dealer right down the street from me and made a deal with them. The only thing I paid for was parts, and my bill was less than $400 for a $1500 repair.

20,000 miles later the noise was starting to come back. I traded it in on a F-250 before I could find out how much worse it would have gotten.

 

[Will]

It started to come back because there is a chain in the rear too and they didn't replace that one. I think the TSB for that said only do the front chain. That makes the noise half as loud I guess. The '97 Explorer I was involved with had all the nylon tensioners in the oil pan when I took it apart. I wouldn't touch an early one with a ten-foot pole.

 

[Jspafford]

It started to come back because there is a chain in the rear too and they didn't replace that one. I think the TSB for that said only do the front chain. That makes the noise half as loud I guess. The '97 Explorer I was involved with had all the nylon tensioners in the oil pan when I took it apart. I wouldn't touch an early one with a ten-foot pole.

Your probably correct. I know they pulled the motor to do whatever they did though. I had to take it back a week later because it was leaking antifreeze.

I loved that truck though, I did a title search on it the other day and it is still running and has over 100K on it now.

It handled and performed like a mustang but was desguised as a pickup.

I used to love taking off from a stop, letting off the gas, and then flooring it. Could roast tires on command.

Man I miss that truck.

 

[krikf]

I had seen similar comments on this board about 3 months ago when I first started looking for a 4.0 SOHC. I thought that everyone at that time said that it seemed all timing chain issues were fixed by the 2003 model. This is a 2004 I'm looking at but now you have me second guessing whether the 4.0 SOHC is the way to go. I'm a 3rd generation Ford only guy so I was planning on staying w/the Ranger line if at all possible.

 

[Jspafford]

Mine was a 2001 model.

 

[Will]

When these motors first came out in Rangers we were here. There were lots of rattling problems with them and lots of theories. There was a lot of tensioner trouble in the end. While I haven't heard anything bad about them in a long time, it doesn't mean a newer truck can't have the trouble. A SOHC 4.0 has a lot of chains. There is a chain that drives a jackshaft from the crankshaft--that's were the timing chain is on pushrod motors--the jackshaft is riding in the old camshaft bearings. Then on each end of the jackshaft there is a long chain that goes up to the cylinder head to drive the camshaft for its respective head. Then, on a 4x4, there is a balance shaft that is in there to cancel vibrations. Even if they now have a suitable recipe for the tensioners, there could have been a problem in that particular truck that has nothing to do with it. I wouldn't buy a 2004 with a bad knock, rattle or any sort of music--pop, swing, rythm and blues or John Denver coming out of the motor. These motors aren't going to have bad detonation on them without throwing a light. A light growling in the wrong gear on a hill is one thing. A bad knock or rattle above 3,000 is not detonation.

 

[krikf]

Rattle answer

In case anyone is interested, my mechanic friends at the Ford dealer found that the rattle is a really bad spark knock. There is one tech bulletin dealing with this issue on this year/model but they said it doesn't always fix the problem. Because it may take multiple parts replacements they suggested not buyiny this one until the dealer has it fixed if he will. Guess I'll pass on this one.