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Discussion Starter #1
So after 20K miles of ticking my cam is toast. I have 115K on my rig and have run Royal Purple some of her life tho I started the first 80K on Mobil 1. Turns out these engines need zinc (I believe) in the oil which Amsoil and RP have but the M1 is not ideal for the 4.0.

Not sure how many of you out there are having cam issues but apparently it's common for the 4.0 and boy am I bummed out, gonna cost a few grand to get her back on the road. That cost does include a programmer and throttle body but most of it is labor. I am wondering if anone has changed their cam their self and if so how difficult of a job is it? I know it's gonna be a bitch but wondering if I can do it with regular tools in my garage? Any upgrades I should consider while I have her apart?

Thanks for any direction. Brian
 

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Re: Need advice... cam shafts are done.

I held out to start a thread and then finally do... three minutes later see the other cam shaft thread. :oops:


Still want to hear any wisdom you may have to offer. Thanks
 

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Re: Need advice... cam shafts are done.

FWIW... I'm sure you've seen DoctorDs thread on oil. But Mobil1 10-30 high milage with ACEA A3 certification has the "goodies" in it that our engine requires. There are other ACEA A3 oils out there, but not many. And you literally have to look for the certification on each bottle cause you can find some bottles that do and some that don't meet that standard.

As for cam shaft options, don't think you have many choices in brands. But I would check out Hesco if I were in your shoes and maybe even seek their advice.
 

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Re: Need advice... cam shafts are done.

I would be interested in what you find out . why do you think its the cam, could it be a lifter sticky or a rocker arm? is it missing?
 

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Re: Need advice... cam shafts are done.

The work to actually change the camshaft isn't bad, but can take some time. You'll want to look over the head and valves in particular. Fix anything wearing out on the top end while you have it apart.

I think the difficult part is getting the synch correct on the distributor housing, if you do it yourself.
 

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Re: Need advice... cam shafts are done.

I haven't done one in this 4.0 but have in several 350 chev's in the past. Granted not exactly apples to apples but at the same time, not particularly difficult, just time consuming. As was mentioned, getting that sync from the dealer will be the hard part as it kinda has to be at the dealer to do that.

I'm curious though-can you buy that computer tool to do this at home? When I replaced my CPS in the dealer lot, I basically did all the work and had the techs watching to see what was going on and how things worked as they didn't have a clue. When it came to sync'ing the cam, all we did was watch the computer and twist/turn the new CPS just a hair till we had it in spec. Not sure if there's a tool like that or similar that you could buy to do this yourself-it would be a heck of a lot easier for me and would save many trips to the dealer for computer work...

What makes you think the cam is bad? I have a misfire on #2 I can't eliminate regardless of what I do and have been thinking cam myself and/or bad lifter/spring.

Somebody posted some pretty nice specs on a Hesco setup that made some impressive torque numbers down low and peak torque at 3200 or something. I'd look to them for parts.

Best of Luck,

Mike
 

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Re: Need advice... cam shafts are done.

Bookie said:
I would be interested in what you find out . why do you think its the cam, could it be a lifter sticky or a rocker arm? is it missing?

I will keep ya'll posted on the actual damage. It's losing power and the fifth and sixth are missing, runs lean (has since I bought it new didn't know it early on tho) and has ticked for 30K miles now... come to think of it I had warranty service back in 2004 leaving Moab (ROF's first annaul Moab meet.. never happened again officially) in Denver while heading back to TN, the engine was running very lean and the dealership couldn't figure out why? had 35700 miles on the ODO for documentation purposes. I wrote it off as my computer was adjusting to the altitude but really the engine has always run lean, I wonder if this could help me out at Jeep?... not counting on it. :laugh: My Jeep guy (Extreme Gear Offroad) seems to think a push rod could be bent and is fairly certain (without pulling anything apart) that it needs new cams. He has four 4.0L motors with less than 40K sitting around his shop needing new cams (one only has 12K) most just swap at that point to the Hemi but with all the extras I have in my engine compartment I want to stay with this motor at least for this rig.


I was looking at buying a brand new 2011 Sahara 4 door with the new interior but I am so livid with Chrysler that I may not buy another new Chrysler product as long as I live. :roll:
 

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Re: Need advice... cam shafts are done.

Another come to think of it... was my engine ticking started about a year after I moved to an elevation of 7000 feet, I wonder if this made the engine work harder and after a years time or so the engine started to "officially" break down. I may start to drive myself crazy if I think too hard on this one. :?


I am looking into Hesco for replacement parts, thanks for the heads up guys.

Thanks for the advice thus far it has been very helpful.
 

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Re: Need advice... cam shafts are done.

you can check with just pulling the valve cover and using a tool i wana say i dial mic but i know thats not it and palnce on the rocker arm and check travel to see if one or more lobes or lifters dont have the same travel that will identify if you have a worn cam lobe or lifter face ill post up some pics of what happened
 

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Re: Need advice... cam shafts are done.

you are close its called a dial indicator and yes thats bestway to check cam lift without takeing everything aparthttp://www.harborfreight.com/1-inch-travel-machinists-dial-indicator-623.html

no need for an expensive one for a job like this,


another thing is if the cam is that bad you will have a miss with it, thats why I asked earlier, just noise means its going bad or something else is makeing the noise
 

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Re: Need advice... cam shafts are done.

Just pulled my OPDG and tho I was surprised how well mine looked after 115K it will need replacing along with the cam shaft. When I took it down to Extreme Gear to get the Banks Header installed it started that churp noise and I thought it was a pully or the belt just figured out it's the OPDG (Extreme Gear didn't know what it was).

I spoke with Benny today at Hesco and more than likely going with their cams, push rods, lifters, performance valve springs and retainers and switching to single groove valves (due to the cams being .470 lift). I will need my cylinder heads machined (or valve ends or something like that... this is not my are of expertise by no means) and labor is looking to cost $940 plus another $280 for the oil pump to be changed out (may do that myself). Parts from Hesco are looking to top $800 plus shipping.

After speaking with Hesco my issue may not so much be Chryslers fault as the governments for regulations to mandate reductions in the zinc content of our early synthetics as synthetics started to become all the rage (suppose Chrysler was a victim just as I am... did I just really say that...) of more government regulation put on by the pinheads in Washington. Now the new rage (or advertising at least) is the added zinc in the synthetics. :roll:
 

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Re: Need advice... cam shafts are done.

Few shots, sorry for the poor pic quality

OPDG






Cam

*edited in new pics



 
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