3.7 L engine
considering buying '07 Grand Cherokee Laredo 3.7 L engine, 4 x 4, 67K miles. My Mech. says stay away from the 3.7 L engine. they are a nightmare to work on. I would like to know if others have had same problems?
Old fart with a wrench
Joined: Nov 2010
Posts: 14,398
Likes: 740
From: Manlius, east of Syracuse, NY
Year: 2000 XJ Sport & WJ Laredo
Model: Grand Cherokee (WJ)
Engine: 4.0L
Welcome to CF!
First of all, most modern engines are getting quite complicated to work on. Having said that, let's talk about the 3.7. This engine is nothing more than a 4.7 minus 2 cylinders, as in OHC aluminum head, iron block, chain driven nightmare to work on. They have a history of warped heads and blown head gaskets, dropped valve seat inserts, and broken timing chain guides. Many people have no problems with them, but when problems DO appear, they can be costly to fix.
JMHO, but my experience is with basically bullet-proof Chevy small block V8s and Jeep 4.0 straight 6s, so I don't trust these "new-age" engines at all. As with all engines, maintenance is the key to longevity, but these new engines require more than most.
I think the key to buying a used car of any kind is how it's been treated before you bought it. Again, just my opinion, but if it's been neglected, stay away from it unless you're willing to work on it.
First of all, most modern engines are getting quite complicated to work on. Having said that, let's talk about the 3.7. This engine is nothing more than a 4.7 minus 2 cylinders, as in OHC aluminum head, iron block, chain driven nightmare to work on. They have a history of warped heads and blown head gaskets, dropped valve seat inserts, and broken timing chain guides. Many people have no problems with them, but when problems DO appear, they can be costly to fix.
JMHO, but my experience is with basically bullet-proof Chevy small block V8s and Jeep 4.0 straight 6s, so I don't trust these "new-age" engines at all. As with all engines, maintenance is the key to longevity, but these new engines require more than most.
I think the key to buying a used car of any kind is how it's been treated before you bought it. Again, just my opinion, but if it's been neglected, stay away from it unless you're willing to work on it.
Last edited by dave1123; Oct 17, 2016 at 08:47 PM.
Seasoned Member
Joined: Dec 2015
Posts: 467
Likes: 6
From: Sioux Falls, SD
Year: 2001
Model: Cherokee (XJ)
Engine: 4.0l
Welcome!
My '05 Ram has the 3.7L in it with 155K on it. I have not had any engine problems with it - I can't attest whether or not the engine is a nightmare to work on as I've never had to!
I used to work at a TV news station that had two Jeep Liberty's with the 3.7L for the news team. Both were somewhat abused (driven hard with minimal maintenance) but were always reliable. One had 220K before it was replaced. The other was still going strong with 175Kish when I left.
So my experience with the 3.7L has been positive, but I may have been one of the lucky ones.
My '05 Ram has the 3.7L in it with 155K on it. I have not had any engine problems with it - I can't attest whether or not the engine is a nightmare to work on as I've never had to!
I used to work at a TV news station that had two Jeep Liberty's with the 3.7L for the news team. Both were somewhat abused (driven hard with minimal maintenance) but were always reliable. One had 220K before it was replaced. The other was still going strong with 175Kish when I left.
So my experience with the 3.7L has been positive, but I may have been one of the lucky ones.
Old fart with a wrench
Joined: Nov 2010
Posts: 14,398
Likes: 740
From: Manlius, east of Syracuse, NY
Year: 2000 XJ Sport & WJ Laredo
Model: Grand Cherokee (WJ)
Engine: 4.0L
I sort of knew this was coming! Of course many people have good luck with them, but I just recently saw a Jeep Liberty torn apart because a timing chain guide (plastic) broke and the chain jumped destroying all 3 pistons and the valves on one bank.
Senior Member
Joined: Feb 2012
Posts: 884
Likes: 46
From: Baltimore
Year: 2002
Model: Grand Cherokee
Engine: 4.0L (AMC) Straight Six
If you're going to buy a WK (2005-2010) Grand Cherokee, I'd highly recommend looking for one with the 5.7L HEMI V8. In my opinion that was the only good engine in these Jeeps.
Trending Topics
Seasoned Member
Joined: Dec 2015
Posts: 467
Likes: 6
From: Sioux Falls, SD
Year: 2001
Model: Cherokee (XJ)
Engine: 4.0l
That sounds fun. It seems to me that the 3.7L/4.7L are very hit or miss engines. Some people swear by them, some people swear at them.
Senior Member
Joined: Mar 2016
Posts: 707
Likes: 20
From: AV Kalifornia
Year: 1996
Model: Grand Cherokee
Engine: 4.0
CF Veteran
Joined: Jan 2012
Posts: 2,208
Likes: 5
From: Ocean County, NJ
Year: 1998
Model: Cherokee
Engine: 4.0L
ugh I hate 3.7's. Garbage. Just did the heads on the wife's liberty at 135k miles because it overheated and pushed the gaskets out. I can go on and on and on about how much these things suck. Had a friend with one and it first lost the waterpump but did not overheat. It then loved to mysteriously lose coolant. Never really had a chance to dig into that one. I'd stay far away from them if I could. Can't wait to get rid of the wife's Liberty.
Old fart with a wrench
Joined: Nov 2010
Posts: 14,398
Likes: 740
From: Manlius, east of Syracuse, NY
Year: 2000 XJ Sport & WJ Laredo
Model: Grand Cherokee (WJ)
Engine: 4.0L
Wait just a minute! The K-car was a POS rolling tin can, but it kept running! That 4 cylinder kept running long enough for my wife to drive it home with a completely plugged converter! It blew the EGR valve completely off the manifold and popped the head gasket, but it still ran! I replaced the head gasket, converter and EGR valve and she drove it for another year and a half. As a matter of fact, she drove it to Orlando and back after me telling her not to! She hit some black ice and folded it around a tree, then bought a Caravan, one of Lee's better ideas.
Thread
Thread Starter
Forum
Replies
Last Post
ERICH128
Stock Grand Cherokee Tech. All ZJ/WJ/WK Non-modified/stock questions go here!
1
Sep 3, 2016 12:28 AM
Doug Propst
Aftermarket electrical systems
3
Aug 21, 2016 12:38 AM
John Benfer
Stock Grand Cherokee Tech. All ZJ/WJ/WK Non-modified/stock questions go here!
0
Aug 20, 2016 10:34 AM
Currently Active Users Viewing This Thread: 5 (0 members and 5 guests)



