Changed OPDA but my camshaft gear has wear. Need a dose of reality.

Jae Spartacus

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I opened the hood and showed the new OPDA to the old one and also showed it a wrench. I think the threat is enough to keep it in line.
Got a good laugh out of that one, thanks needed that! I've been deciding whether or not I should get the Crown unit just in case—this is enough of a reason to get it :ROFLMAO:
 
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fizzlebottom

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Well it might? but a thousand other computerized gremlins will make you wish it did sooner! :)
I'll cross those electrical bridges when I get there. I need to tackle three ready shocks next, but I'm really not in a hurry. I think the OPDA was the last pressing thing for now. Hopefully.
 

JeepZilla380

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Today is year 7 with my 2005 LJR. When I first got her I read all the disaster stories with OPDAs and after some chirping noises (which later was discovered something belt driven) I proactively replaced my OPDA. I even had another belt driven chirp a few years later that prompt me to get a 2nd OPDA to just leave on the shelf. I had some wear on the cam when I swapped the first OPDA, but never had another issue. So my thought is if you get a 05/06, just but the Crown for a piece of mind, and make sure you use the original OEM sensor.
 
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fizzlebottom

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Today is year 7 with my 2005 LJR. When I first got her I read all the disaster stories with OPDAs and after some chirping noises (which later was discovered something belt driven) I proactively replaced my OPDA. I even had another belt driven chirp a few years later that prompt me to get a 2nd OPDA to just leave on the shelf. I had some wear on the cam when I swapped the first OPDA, but never had another issue. So my thought is if you get a 05/06, just but the Crown for a piece of mind, and make sure you use the original OEM sensor.
I used my original sensor. It didn't want to come out at first which made me nervous. I read one or two accounts of people's MOPAR sensors crumbling when they removed them. But some patience helped and it eventually released from its 16 year home.
 
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NOTNSUV

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I have a 2006 TJ Unlimited with 236k that was running then original OPDA before I changed it to the crown unit. I’m sure it probably wasn’t needed, but I did it for peace of mind. It ran great before the swap and runs great after.
So at 30,000 miles I suppose it's silly to change the OPDA as preventive maintenance? Any reports of very low mileage OPDA failures.

Maybe I'll install iridium plugs and call it a day. The Crown unit can collect dust.
 

Fishtaco

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So at 30,000 miles I suppose it's silly to change the OPDA as preventive maintenance? Any reports of very low mileage OPDA failures.

Maybe I'll install iridium plugs and call it a day. The Crown unit can collect dust.
I think the original failures were on low mile engines. If you have the crown unit you may as well change it out sooner than later, for most its a pretty simple swap. I was apprehensive myself to swap parts on a a good running motor until I got a start-up squeal one morning and then I whished I had changed my shelved crown unit sooner.

My squeal could have just been a belt on a moist morning but who knows?
 

Lax22

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So at 30,000 miles I suppose it's silly to change the OPDA as preventive maintenance? Any reports of very low mileage OPDA failures.

Maybe I'll install iridium plugs and call it a day. The Crown unit can collect dust.
It’s not so expensive or hard that I would not do it, especially with very low miles. In my case, the Jeep already had high miles on a factory rev. E OPDA and I did not have any symptoms, I just figured I do it for piece of mind. I did have to use a Napa cam position sensor because the crown one was bad and I could not get the OEM sensor out of the housing. So if I were you I would change to the crown opda and swap in your original sensor.
 

NOTNSUV

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It’s not so expensive or hard that I would not do it, especially with very low miles. In my case, the Jeep already had high miles on a factory rev. E OPDA and I did not have any symptoms, I just figured I do it for piece of mind. I did have to use a Napa cam position sensor because the crown one was bad and I could not get the OEM sensor out of the housing. So if I were you I would change to the crown opda and swap in your original sensor.
Except for this:

"This is from @mrblaine : "Most of them are just lucky and get it within tolerable range and it runs. So, they tell everyone since they did it, everyone else can to. We always reset the timing of the unit with a DRB and do the forced relearn. Not one of them put in with even very careful marking and care about orientation is even close to being in spec."

I want to be sure my mechanic can perform the above DRB timing reset and relearn. The reason I'm not doing it myself is there's no way I have the equipment to do that, and close enough is not good enough.
 
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Lax22

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Except for this:

"This is from @mrblaine : "Most of them are just lucky and get it within tolerable range and it runs. So, they tell everyone since they did it, everyone else can to. We always reset the timing of the unit with a DRB and do the forced relearn. Not one of them put in with even very careful marking and care about orientation is even close to being in spec."

I want to be sure my mechanic can perform the above DRB timing reset and relearn. The reason I'm not doing it myself is there's no way I have the equipment to do that, and close enough is not good enough.
True, I guess I was one of the lucky ones but yeah with 30k on your engine I would take it to someone that can get it dialed in 100% with the proper equipment so you know there will be no issue.

To me it was no different than changing a distributor on the older 4.0L engines. I followed some of the how-to guides online and it runs wit no issues. I turned the crank to get the engine at TDC, I pinned the factory OPDA so the shaft wouldn’t move, and marked the housing in a few different spots so I knew the replacement went back in the original orientation. Then just did the reverse, as I said before, my issue was that one of the pins in the crown CAM Position Sensor had pushed out the back of the plug causing poor contact. I replaced it with a Napa unit and all is good.
 
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Jerry Bransford

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Story time :) When I was looking for a TJ Mr Google led me to this Forum every time with quotes from one person who said he would never buy a 2005 or 2006 because of the OPDA problem and said it for many years,
That is me and I still would choose the older year if I was choosing between a 2004 or older and a 2005/6. By choosing the 2004 or older I KNOW I won't have an issue with either the OPDA or the automatic transmission controller. By choosing the 2005/6 I might have the issue. I'd rather not worry about it at all. These threads happen here all the time but they never concern 2004 or older. Period.
 

Lax22

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That is me and I still would choose the older year if I was choosing between a 2004 or older and a 2005/6. By choosing the 2004 or older I KNOW I won't have an issue with either the OPDA or the automatic transmission controller. By choosing the 2005/6 I might have the issue. I'd rather not worry about it at all. These threads happen here all the time but they never concern 2004 or older. Period.
That’s why my TJ is an 03. The 06 rubicon unlimited is the first model I’ve owned over an 04.
 

g.hayduke

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So at 30,000 miles I suppose it's silly to change the OPDA as preventive maintenance? Any reports of very low mileage OPDA failures

The OPDA doesn't typically fail suddenly. What tends to happen based on reports I've read, is that the OPDA can cause excessive cam wear that eventually causes it to throw CEL codes. If you wait for that to happen, you might have to replace the cam along with the OPDA. Sometimes, they start making noise before the wear is excessive but not always.

I bought my Jeep with around 80K miles and it was throwing the code for cam/crank synch. I replaced the OPDA which had some wear on the gear and I could see more wear than I would like on the cam.

I replaced the OPDA per the FSM procedure and used an original CPS. No related codes for around 4 years now. YMMV.

POINT: Waiting for OPDA problems is not advisable. You could end up with a much larger repair bill if you wait too long.
 

NOTNSUV

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Mine is manual FWIW.

Truth is, I'm waiting to find a shop with a DRB scan tool who can reset the timing and do the forced relearn - with input from others here, that is a necessity. The Jeep dealer is one option, if anyone there knows what/how.

Don't want to settle for close enough.
 

Fishtaco

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That is me and I still would choose the older year if I was choosing between a 2004 or older and a 2005/6. By choosing the 2004 or older I KNOW I won't have an issue with either the OPDA or the automatic transmission controller. By choosing the 2005/6 I might have the issue. I'd rather not worry about it at all. These threads happen here all the time but they never concern 2004 or older. Period.
Took you a long time to bite on that one JB :)

Apart from a few YT vids I have not read about a total failure even on here just mostly preventative maintenance changing, some after start up noises some not but yes you are possibly responsible for saving quite a few by your very early OPDA postings, self included as I bought my crown unit almost as soon as I bought my 06 but it would be good to see just how many 05/06 actually failed causing irreversible cam damage given there seems to be a fair amount of high mileage on here that did not fail, my thoughts are the 05/06 gets a bum rap on mr google search forever unless of course its an LJ or a Rubicon.
 

RoscoeJack

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Mine is manual FWIW.

Truth is, I'm waiting to find a shop with a DRB scan tool who can reset the timing and do the forced relearn - with input from others here, that is a necessity. The Jeep dealer is one option, if anyone there knows what/how.

Don't want to settle for close enough.
Please explain.