Hey guys, looking at buying a 2000 QC 4x4 with a 4.7 motor. currently it looks like it needs front diff work. what kinds of problems are you guys seeing on the 4.7 motor and if any in the front diff? any feedback is greatly appreciated.

also, what mpg could I expect with the 4.7 (hiway)

 

pics of the truck...

[IMG]local://upfiles/1508/14E34A5A95F242C782A092E0CF03AB64.jpg[/IMG]

[IMG]local://upfiles/1508/AA683D289C4F41E3A926FFC041A91AA7.jpg[/IMG]

[IMG]local://upfiles/1508/2519AE94DABA47AB993948FFAFBA0798.jpg[/IMG]

[IMG]local://upfiles/1508/D3B0F9A2D8234985A3F3D075A103A947.jpg[/IMG]

[IMG]local://upfiles/1508/BFAF9C9710F74DE3B523B54EBE882653.jpg[/IMG]

 

none of you guys have a 4.7 motor? [sm=confused06.gif] [sm=popcorn.gif]

 

Watch out for the dreaded valvetrain noises, and piston slap. My MPG average is around 15.

 

Thanks! did anyone find out why there is piston slap? piston skirts too short? what rpms would I hear it at?

what about the valve train noises? anyone figure it out yet?

 

I havent had any problems with mine at all. (knock on wood) I get around 18 on the highway, depending on how many people I pass and how fast I go.

 

Most feel that the valve noises are from the lash adjusters, and on the piston slap... no one has the answer, that I have read. These problems seem to happen to very well kept motors as well as the neglected, and not necessarily to justhigh mileage motors. So, you rolls the dice, you takes your chances.
Mine makes the valve noises for around 40 seconds on cold start up. However, the knocking that is said to be piston slap, sometimes clacks a few times here and there for upwards of 3 minutes. I hope the engine warranty I bought pays off when this thing decides to 'belly up'.

 

no problems yet heard that there very reliable engines i average about 17-18 cityish and 19-21 highway with the stick

 

everyone who has had the noises in the motor, are they most likely using the 5w30 oil? I always use 15w-50 mobil 1, regardless of what the mfg specs. never had any issues internally on any motor since using it.

On the 5.x's we all know they have plenum & cracked head problems... is there anything like that with the 4.7?

thanks everyone for the feedback. I went ahead and picked it up. seems cheep enough to be able to fix the problem it has and get it dialed in for long term use.

 

The reading I did, indicated that going with a thicker oil did nothing to quiet things down. On the good side, no one stated having cracked heads, and the 4.7 has no plenum thang.
Post up a 'run down' of your 'new' truck for us, after you get to play around with it some.