- Location
- Austin, Texas
Okay, so I recently (gulp) bit the bullet and had my 4.0 replaced with a Jasper reman due to an increasing rod knock. With the new engine in, it sounds better, but there are a few rough spots. Would love opinions.
#1. Driving it back from the garage in the Texas heat, I was noticing concerning oil pressure numbers on hot idle. Cold start and non idle pressures are 45-50psi, so far so good. But when fully hot and idling, gauge was reading around 11-12psi, just out of spec. I changed the oil at 50mi with PYB 10w30 and changed the Champion filter they installed with a Wix. Sticking with conventional oil until about 5k miles. That seems to have brought hot idle pressure up to ~15psi. Is this good enough for a new engine or do I have other things to worry about?
#2. I had the clutch replaced while the motor was out. With the new motor and clutch, I'm getting more vibration in the clutch pedal than I was on the old motor. And, starting from a stop in 1st, its pretty hard to avoid a shudder in the drivetrain until it gets moving. Doesn't seem to be RPM dependent as it doesn't do it in other gears. What might be causing this?
Other than that, I'm liking the new engine well enough. Feels like the old one but without the knock.
1998 4.0, AX15 btw.
#1. Driving it back from the garage in the Texas heat, I was noticing concerning oil pressure numbers on hot idle. Cold start and non idle pressures are 45-50psi, so far so good. But when fully hot and idling, gauge was reading around 11-12psi, just out of spec. I changed the oil at 50mi with PYB 10w30 and changed the Champion filter they installed with a Wix. Sticking with conventional oil until about 5k miles. That seems to have brought hot idle pressure up to ~15psi. Is this good enough for a new engine or do I have other things to worry about?
#2. I had the clutch replaced while the motor was out. With the new motor and clutch, I'm getting more vibration in the clutch pedal than I was on the old motor. And, starting from a stop in 1st, its pretty hard to avoid a shudder in the drivetrain until it gets moving. Doesn't seem to be RPM dependent as it doesn't do it in other gears. What might be causing this?
Other than that, I'm liking the new engine well enough. Feels like the old one but without the knock.
1998 4.0, AX15 btw.
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