My Jeep GC 4.7L......RIP

[fcjeep]

Sadly,last Tuesday,my beloved Jeep suddenly and without warning dropped a valve seat (maybe several) and bit the dust. Engine is toast....just like that!

I ran a bunch of errands that day and made several stops. Truck ran as smooth as it always had for years. On a restart, out of the blue, it ran very rough and would barely idle. The CEL began flashing so I shut it down. My scanner showed a code of "P0300-random misfire". I thought it was a computer or sensor or ignition issue. Had it towed to a trusted mechanic who gave me the bad news the next morning. A video from the borescope proved him right.

I know the valve seats on these motors can drop if overheated but the truck NEVER EVER came close to overheating in its entire life and I'm the original owner. What a major disappointment from my truck that I maintained so well and was sooo reliable for 153,000 miles.

Still can't believe this happened. I thought for sure it would have made it to 200,000 miles and beyond. SMH.

 

[dlundblad]

I passed on a clean 4.7 Grand Cherokee last spring just because of the valve seats. And I know I would probably speed and get many tickets, but that's another story.

They seem to just die for whatever reason. Very sad though.. especially seeing that you're the original owner.

RIP.

Are you just scrapping it?

 

[jeepman3071]

Manufacturing and materials failures are the worst, because they usually happen with no warning, and regardless of how the vehicle was maintained.

 

[JC1]

A coworker of mine had the same thing happen to his charger. Got the motor rebuilt. He said the new seats are pinned In place.

Wonder if the newer V8s from Jeep/Chrysler have this desin flaw fixed.

 

[jeepman3071]

Originally Posted By: JC1
A coworker of mine had the same thing happen to his charger. Got the motor rebuilt. He said the new seats are pinned In place.

Wonder if the newer V8s from Jeep/Chrysler have this desin flaw fixed.


The problem happens in the 4.7L and early 5.7L V8s. I believed the issue was fixed with the later 5.7L's in about 2008 or so.

 

[fcjeep]

Not sure what I'm doing with it yet.

This came at a bad time. I've been in the middle of a personal family issue for several months and don't have a clear mind to figure what to do right now. A remanned Jasper motor is $5900 pl tax.

 

[fcjeep]

You're right. It also happens with the 3.7L as that's the 4.7L with 2 less cylinders.

 

[dlundblad]

Originally Posted By: fcjeep
Not sure what I'm doing with it yet.

This came at a bad time. I've been in the middle of a personal family issue for several months and don't have a clear mind to figure what to do right now. A remanned Jasper motor is $5900 pl tax.


No way. Get a low mileage salvage yard engine.

I don't go to a mechanic for much, but the one I do trust installed an 80k 4.0 in a 1999 Cherokee for $1800 plus tax out the door. He uses a huge salvage yard in Chicago/ Michigan City area.. Just to give you an idea.

 

[jeepman3071]

It all depends if Jasper fixes the problem. You don't want to go through this to possibly have it happen again (if you plan on keeping the Jeep). From what I've heard about Jasper on here they don't inspire much confidence.

Not sure why, but that seems high for a rebuilt 4.7L. Maybe it has just been a while since I priced one out. I second the idea of finding a verified low mileage salvage engine. Sometimes you can find one from a crashed vehicle that you can still hear run and see the odometer. The 4.7 was used in a variety of Jeep and Dodge vehicles.

It's a shame this happened, because otherwise the 4.7L is a pretty nice engine. Good acceleration for it's size and not bad on fuel. My dad had one in his 1999 Grand Cherokee that he sold with 180k.

 

[JustN89]

Originally Posted By: fcjeep
Not sure what I'm doing with it yet.

This came at a bad time. I've been in the middle of a personal family issue for several months and don't have a clear mind to figure what to do right now. A remanned Jasper motor is $5900 pl tax.

JASPER = NEVER AGAIN

 

[dlundblad]

Originally Posted By: jeepman3071
It all depends if Jasper fixes the problem. You don't want to go through this to possibly have it happen again (if you plan on keeping the Jeep). From what I've heard about Jasper on here they don't inspire much confidence.

Not sure why, but that seems high for a rebuilt 4.7L. Maybe it has just been a while since I priced one out. I second the idea of finding a verified low mileage salvage engine. Sometimes you can find one from a crashed vehicle that you can still hear run and see the odometer. The 4.7 was used in a variety of Jeep and Dodge vehicles.

It's a shame this happened, because otherwise the 4.7L is a pretty nice engine. Good acceleration for it's size and not bad on fuel. My dad had one in his 1999 Grand Cherokee that he sold with 180k.


Jasper: Never again!!!

 

[fcjeep]

I don't want to get a salvage yard 4.7 because it will still have the same design flaw and this could happen again. Thought about doing the heads but the cylinder wall appears damaged and I don't even know about a few other cylinders. Could be a lot of labor for nothing.

And I've read a lot of mixed reviews about Jasper but my mechanic likes 'em.

 

[fcjeep]

My understanding is that Jasper fixed the problem. If the fix works I don't know.

The price includes the installation and a new intake manifold and an install kit which I haven't been able to find out exactly what that is yet.

 

[Chris142]

Another thing worth mentioning. When this happens hot pieces of seat get blown into the plastic intake manifold where they cool and melt into the manifold. Eventually they work out and get sucked into a cylinder and it blows up again. You must replace the intake manifold along with the new engine or it will happen again.

 

[OneEyeJack]

Let us know what you end up doing.

Something as basic in design as a valve seat should not be a problem either in design or manufacturing and assembly.

Would the problem have been solved in a later model vehicle making a junkyard engine a reasonable solution?

 

[HawkeyeScott]

Sorry that happened. I say this knowing the easiest money to spend is someone else's, but I'd encourage you to think about reinvesting in the Jeep. Especially since you know its full history. There's a lot of value in that.

Best of luck with all matters at hand. Hang in there.

 

[OVERKILL]

Originally Posted By: OneEyeJack
Let us know what you end up doing.

Something as basic in design as a valve seat should not be a problem either in design or manufacturing and assembly.

Would the problem have been solved in a later model vehicle making a junkyard engine a reasonable solution?



Ford had the same problem (dropping valve seats) on the older engine in the Focus. It's surprisingly not that uncommon

 

[skyactiv]

I definitely wouldn't drop $5900 into it. If someone smashed into it 5 minutes after pulling out of the shop with the replacement engine, you wouldn't get what you put in it if it got totaled.

 

[eyeofthetiger]

Originally Posted By: skyactiv
I definitely wouldn't drop $5900 into it. If someone smashed into it 5 minutes after pulling out of the shop with the replacement engine, you wouldn't get what you put in it if it got totaled.


The same could be said for any new car. That's what gap insurance is for.

 

[MParr]

What would it cost for a reputable engine builder to rebuild it and slap some performance heads on it? It may be worth investigating.