Join Date: Jun 2008
Location: Cincinnati, OH
Vehicle: 2002 Durango SLT+ 4.7L V8
Modifications: HO Cams, Superchips, 5-45rfe TCM mod.
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 16 Post(s)
The rattle could be the timing chains.
It could also be valve lifters.
The timing chain guides have plastic. (Nylon or Phenolic) surfaces. They could be pretty worn and need replacement.
Additionally, If the oil pressure is lower, the ratcheting pawls might be a bit slow to extend and push against the chain.
Did you take oil pressure readings?
They would be good numbers.
You will want to put a mechanical gauge on it and watch it from a cold start and from a hot start.
Just plain old engine wear:
The oil pump might be have enough wear to be contributing to the problem.
At those miles, you might need to go up in the viscosity range to keep the oil pressure up.
5w-30, and even 10w-30 (Factory recommended) might be too thin at this point in the engine's life.
You might want to go to a 15w40 or straight to a 20w50. A tired oil pump will do better with oil in those ranges.
You are long overdue to change the fluid and both filters. You should do it. (No need to flush or anything like that.)
Leak from front:
Change the timing cover seal. Put new timing chain guides on it while you are there (If it needs them).
I guess if it needs to be replaced... It needs to be replaced. There is so much stuff that needs to come off on a 4WD to do this. I am sure it is an expensive job.
Good luck with it.
Member of the engine rebuild club, HO Cams, 68mm TB by Dwight, SuperChips, Bilstein shocks, 5-45rfe Jeep TCM mod. ... and I clean the windows pretty often.