What Did You Do To Your 2ND GEN RAM Today?
#8621
#8625
Join Date: Mar 2011
Location: Fredericksburg, Virginia
Posts: 8,914
Likes: 0
Received 2 Likes
on
2 Posts
i think Hammer might tell you to avoid something like that since those 4.7 like blowing up.
https://dodgeforum.com/forum/jeeps/3...p-carnage.html
https://dodgeforum.com/forum/jeeps/3...p-carnage.html
#8626
#8627
Join Date: Jul 2007
Location: South Georgia/East Florida
Posts: 24,686
Likes: 0
Received 20 Likes
on
19 Posts
The 4.7 is a crap shoot IMO. First off- aluminum heads that can't take even a mild overheat.
Yes, we have Dak and 3rd Gen Ram and others with 4.7s in them with well over 150k miles on them without issue - and odds are you won't if you never let it overheat.
Now in my case I NEVER saw my temp gauge go over 230* which it went up to once when my radiator split. Also, after installing a front receiver hitch, my normal running temp went up from about 205* to about 215* because the receiver blocked about 4" across the bottom of my radiator.
Techs are split on whether it was the one time at 230* or sustained temps over a few years at about 10* above normal that caused the head to fail. The failure specifically was the soft aluminum head expanded just enough to drop the hardened steel valve seat.
Shame too because I loved that Overland Grand Cherokee. Plush as hell inside and because it was an Overland it had the HO version of the 4.7 with about 60 more HP/TQ. PLUS that edition and the Wrangler Rubicon are the only two Jeeps to come with lockers in both axles. Even though my truck is taller and has WAY more aggressive tires, that Jeep would go through muck that I'd have been winching my truck out of.
In either case, I think an engine that will sustain a head failure at 230* or running a lousy 10* over normal is a pretty **** poor design and I recommend to stay away from it. BTW, the 3.7 is exactly the same but 6 cylinders.
Not to mention that when I rebuilt this sucker I'm now convinced I'll NEVER own a OHC engine again. Way harder to work on than a good old push rod engine - which for those who don't know, yes the 5.7 Hemi is a pushrod engine...
I agree. I've had four 4.0 I6s through the years and NEVER had an engine issue. ONLY PROBLEM is they are mated to a crappy automatic transmission. You'll go through four tranny rebuilds before the engine quits. The former Mrs. Hammer drove three Grand Cherokees during the 14 years we were together and two had the 4.0.
Now IF you can find a 4.0 with a good old manual tranny - you'd have you something. Both of my Wranglers were such. Problem is, a manual transmission is not an option on a Grand Cherokee...
Yes, we have Dak and 3rd Gen Ram and others with 4.7s in them with well over 150k miles on them without issue - and odds are you won't if you never let it overheat.
Now in my case I NEVER saw my temp gauge go over 230* which it went up to once when my radiator split. Also, after installing a front receiver hitch, my normal running temp went up from about 205* to about 215* because the receiver blocked about 4" across the bottom of my radiator.
Techs are split on whether it was the one time at 230* or sustained temps over a few years at about 10* above normal that caused the head to fail. The failure specifically was the soft aluminum head expanded just enough to drop the hardened steel valve seat.
Shame too because I loved that Overland Grand Cherokee. Plush as hell inside and because it was an Overland it had the HO version of the 4.7 with about 60 more HP/TQ. PLUS that edition and the Wrangler Rubicon are the only two Jeeps to come with lockers in both axles. Even though my truck is taller and has WAY more aggressive tires, that Jeep would go through muck that I'd have been winching my truck out of.
In either case, I think an engine that will sustain a head failure at 230* or running a lousy 10* over normal is a pretty **** poor design and I recommend to stay away from it. BTW, the 3.7 is exactly the same but 6 cylinders.
Not to mention that when I rebuilt this sucker I'm now convinced I'll NEVER own a OHC engine again. Way harder to work on than a good old push rod engine - which for those who don't know, yes the 5.7 Hemi is a pushrod engine...
Now IF you can find a 4.0 with a good old manual tranny - you'd have you something. Both of my Wranglers were such. Problem is, a manual transmission is not an option on a Grand Cherokee...
#8629
#8630
Join Date: Jul 2007
Location: South Georgia/East Florida
Posts: 24,686
Likes: 0
Received 20 Likes
on
19 Posts
IMO 160* is too cool, but a 180* isn't a bad idea. BUT if the thing is going to overheat, the thermostat temp just buys a little time because it'll start from a lower temp is all.
I think the best thing to do with these aluminum head, OHC engines is to be over zealous on the maintenance of the cooling system and just as importantly instill in your wife that if the thing ever starts to overheat on her to shut it down ASAP. DO NOT try to make it home!
You can fix whatever is the cause of it overheating even if the radiator splits at the center seam as my did a LOT less expensively than rebuilding the engine and having the heads re-manned. Or even if it just blows the head gasket it takes about 10 hours to remove the heads on these OHC engines. Been there, done that...