Timing chain rattle 03 sport trac 132K miles

[Boonie2]

Just bought an 03 Sport Trac 4.0 XLT ,132,000 miles a few months ago , changed the oil to Castrol 5w30 full synthetic , Love the truck , but I'm really concerned about the "Startup" Rattle.. Only happens if it sits overnight , never hear a thing when driving . From what I'm seeing here and other places , the guides for the 3 timing chains are plastic and Tend to wear our causing this noise.. How concerned should I be about this rattle ? How common is it for these to break ? I guess I have a decision to make either to have these replaced big $$ or find a low mileage engine also big $$ if they DO come apart..
ANY advice / experience would be greatly appreciated

 

[2000StreetRod]

start up rattle

I replaced all of my timing chain components at about 150K miles because my rear cassette and primary chain tensioner was broken.

Your 2003 has improved cassettes compared to my stock 2000 but the rear traction side is still not metal reinforced and when it breaks the chain can slip. The springs on the new hydraulic tensioners are weak and subject to cold start rattle until the oil pressure builds up. I couldn't put up with the sound so I installed a pre-oiler. Now in addition to quiet cold starts the bearings should last much longer since dry starts have been eliminated.

The SOHC V6 is an interference engine so if one of the cassette chains slips enough, pistons will strike the valves. Most members drive their SOHC V6s until they sound like diesel engines before making the difficult (and expensive) decision of correcting the problem.

 

[JuBean]

I am in the same boat but I do get a little rattle while driving.
I started with the tensioners because they are cheap and easy but they had little impact on the noise. The only thing that has helped with keeping the noise (including cold starts) has been the use of an oil stabilizer and driving easy on the skinny pedal.
That is my solution for the last two years until I can find a cheap engine to rebuild and swap in.

 

[boominXplorer]

Make sure you have a Motorcraft filter on it, the cheaper filters don't have a check valve to keep the oil up top.

 

[Tech By Trade]

Also, if you cant afford to repair it properly now, start saving for a reman, or an engine out of a wreck. Its not if, but when she will blow!

 

[Boonie2]

I replaced all of my timing chain components at about 150K miles because my rear cassette and primary chain tensioner was broken.
View attachment 85213
Your 2003 has improved cassettes compared to my stock 2000 but the rear traction side is still not metal reinforced and when it breaks the chain can slip. The springs on the new hydraulic tensioners are weak and subject to cold start rattle until the oil pressure builds up. I couldn't put up with the sound so I installed a pre-oiler. Now in addition to quiet cold starts the bearings should last much longer since dry starts have been eliminated.

The SOHC V6 is an interference engine so if one of the cassette chains slips enough, pistons will strike the valves. Most members drive their SOHC V6s until they sound like diesel engines before making the difficult (and expensive) decision of correcting the problem.

read up on the "pre-oiler" and saw some of your posts on it , i think i might go that way also , Appriciate the heads up on that ! great idea !

 

[2000StreetRod]

electric pump pre-oiler

I like my Accusump but I wish I had installed an electric motor driven oil pump instead. The disadvantage of an electric pump pre-oiler is a port must be made in the bottom of the oil pan and a hose routed from the port to the pump for oil pickup. The advantages are that complete oil changes are simpler and the system is easily pressurized with clean oil after major engine repairs. At the time I installed my Accusump suitable electric oil pumps were rare and expensive. With the current popularity of turbochargers electric pumps are more readily available.

 

[1996EB]

Try the tensioners first. My son bought an 03 Sport Trac in May with 137,000 miles on it. After we did the first oil change (5W30 semi-synthetic) it developed a slight rattle on cold start. Drove it for about two weeks and did another oil change and switched to full synthetic, but it still rattled. Decided to replace the tensioners. Did the rear tensioner first, as the rattle definitely seemed to be coming from the back. No more rattling at all. A fellow Explorer owner remarked on how quiet this engine runs now. I bought both tensioners for about $120 total. I did buy the required deep drive 27mm socket (good quality one) for about $14, as I didn't have that size. The job took about an hour, going in through the passenger side wheel well. For the cost and relative simplicity of the job, you should try this first. BTW, taking a little extra time to remove the plastic inner fender first will make this a happier job.

 

[manimal]

^^ None of the fancy alignment tools, just a special socket? I've been lead to believe that the job requires a virtual Ford dealership toolset.

 

[Kjhadfield]

^^ None of the fancy alignment tools, just a special socket? I've been lead to believe that the job requires a virtual Ford dealership toolset.

1996eb only changed the rear tensioner, from what I have read (mainly from 2000streetrod) was its a simple unscrew and put in new tensioner. Not sure why you would need anything for alignment because it's completely unrelated. If you look at 2000streetrod thread on tensioners and see the picture, you would notice how protruding the tensioner is (for the front thou), so a deep socket will definitely be needed but as far as the rear tensioner goes, that doesn't protrude so I didn't think you would need a deep socket? It seems that the rear is the easiest to get to/remove (via wheel well) while the front takes a little more work (it's near the thermostats hidden and very tight fit). I don't think any special tools are needed for just tensioner, just the sockets to remove them.

I also have engine noise but not sure if it's timing chain related. I was going to replace the rear tension just because and to be safe but keep hearing 2000streetrod say how weak they are and now I'm not sure I should or not (at least till I verify engine noise as timing rattle). Mines is not just on cold start or a certain rpm but anytime engine runs and it doesn't get louder w/ rpms either, just a steady/constant.

 

[1996EB]

1996eb only changed the rear tensioner, from what I have read (mainly from 2000streetrod) was its a simple unscrew and put in new tensioner. Not sure why you would need anything for alignment because it's completely unrelated. If you look at 2000streetrod thread on tensioners and see the picture, you would notice how protruding the tensioner is (for the front thou), so a deep socket will definitely be needed but as far as the rear tensioner goes, that doesn't protrude so I didn't think you would need a deep socket? It seems that the rear is the easiest to get to/remove (via wheel well) while the front takes a little more work (it's near the thermostats hidden and very tight fit). I don't think any special tools are needed for just tensioner, just the sockets to remove them.

I also have engine noise but not sure if it's timing chain related. I was going to replace the rear tension just because and to be safe but keep hearing 2000streetrod say how weak they are and now I'm not sure I should or not (at least till I verify engine noise as timing rattle). Mines is not just on cold start or a certain rpm but anytime engine runs and it doesn't get louder w/ rpms either, just a steady/constant.

Yes, kjhadfield, I only did the rear tensioner so far. I still have the new front one, but it doesn't seem necessary at this time. It doesn't require special tools, as you mentioned. I could have bought a regular 27mm socket, but as I may end up doing the front tensioner too, I went with the deep drive. You should use a torque wrench to torque the new one to the correct spec. To describe this job in simplest terms for anyone who can't envision it (I know you knew what I did), it is in fact like removing a giant bolt and replacing it with a stronger giant bolt, lol. It is a little tricky when installing the new one because it will be under tension as you try to start the threads. Also, note the orientation of the metal O-ring as you remove it. I found it easier to remove the inner fender, than to fight with it to to get the socket on the bolt head. I hope this helps to confirm to anyone else what I recommended. I think that anyone won't have much to lose if they try this. It might help and was pretty cheap compared with letting it get worse and facing a much larger job. If it doesn't help or makes things worse, the actual timing chains were probably too far gone anyway. I'm not really sure if you could make the rattle worse with a new tensioner, but I guess that would indicate that the guides are a real disaster. Also, I didn't just randomly decide to start with the rear tensioner. I listened carefully in various locations around the engine for the noise. I was just about 100% sure that it was the rear one before I started the job, so I wasn't too surprised when just replacing that one solved the issue.