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Discussion Starter · #1 ·
I routinely change oil with synthetic and came across the engine low pressure gauge going on low side. Turns out I’m out 5 quarts of oil. No Leaks, possibly burning it. Now getting what sounds like rod knock or lifter. I do not think it’s the torque converter or flex plate. Seeing as it’s not hitting anything. Taking off the pan seems like a chore since I’d have to lower front axle. Can I get fellow confirmation what sounds like rod knock or something else?
 

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That tap is in and out I would think a rod would be all the time. Try removing belt to eliminate that area for sure. This does not sound that good though.

tap on rev and nothing on decel is rod most times

Tap on decel nothing on accel is wrist pin most times
 

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Discussion Starter · #3 ·
While you can clearly hear it up too and feel more towards pan and similarly to bell housing where converter is sitting. Would it be likely rod knock transferring vibration towards bellhousing? Possible something hitting windage tray? Obviously I may have to lower front differential and remove pan to verify. Knock became more prominent when serpentine belt was removed
 

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That’s not very consistent it’s in and out. Check converter bolts first rule that out. Drop the aluminum brace between pan and trans off and have a look at the bolts will need a 21mm from underneath to rotate crank.
 

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In your second video at 18s there is a different noise, much deeper, and in your last video at start-up. That sounds like a rod knock to me. My 04 had that same knock at start-up, then would go away, ran and drove good, just had noise at start-up. When I pulled the engine and pan, 1 rod bearing had spun and the crank was junk.
 

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Discussion Starter · #8 ·
Turns out bad rod bearing cylinder 7. Prob spun, will remove and inspect. Based on the video and play anyone think I can get away with lightly polishing crank journal and replacing bearing? I don’t expect it to be a permanent fix. I do need the vehicle and still looking at options for a rebuild. Anyone have any success in replacing one rod bearing and polishing crank journal(obviously not aggressive)? If so, how would one determine what bearing size I’d need? Stick to factory spec? I’ve seen people needing to change to oversized bearing. Thankfully it’s the only rod with possible spun bearing. Included vid

 

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I would not do it but if you absolutely have to have the truck I mean it can’t hurt it anymore than it already is I guess. A lite polish if it takes anything more then it’s not worth even trying to rig it. Should be able to stick to factory size or whatever old bearings say if readable. Again this is not suggested at all but it will be up to you at this point.
 

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Discussion Starter · #11 ·
Sorry been busy. Bearing def spun and was a bit damaged. I am not seeing any scoring and crank might still be junk but I’m gonna try and hope for the best. If fails hopefully rod won’t go through block. Waiting for rod bolts to arrive along with plastigaguge. I know it’s not the most accurate but if I can get another 6 months of the motor that’d help. I got some factory spec Manley bearings and new rod bolts. Anyone know the factory bearing clearance? Since the rod bolts are tty.
I ordered new oem ones. After getting plastigauge reading better to just get another set of oem bolts provided clearance passes? I’m aware journal may be out of round or may be just fine. As mentioned I’ll take that risk seeing as how I’m this far.
 

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Discussion Starter · #12 · (Edited)
Is that concave shape on crank journal normal? Or has the spun rod bearing worn the other part of journal down? Mine has a similar shape.
Yours
Drinkware Automotive lighting Wood Tints and shades Tableware
In
Drinkware Automotive lighting Wood Tints and shades Tableware


mine

Liquid Drinkware Fluid Drink Automotive tire


mind the white stuff. After wet sanding 400 couple of runs, tried using metal polish.
 

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Yes, the crank is worn. It is about a 1/8th in lip where the bearing had spun. The bearing was doubled up on the main part of the rod. My crank is junk along with the rod. if yours is worn similar, your crank is probably also junk. Best to get a micrometer and measure it before you try to just put a bearing in.
 

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I know this is way late but for those still reading this, if you spun a rod bearing your rod is (most likely) now junk and will not hold a new bearing from spinning. On fractured rods like most stock rods now this is not fixable and the rod has to be replaced. If the rods are aftermarket and have flat, machined, rod cap mating surfaces, the caps can be ground shorter and the big end of the rod re-honed at a machine shop to get it back in spec.
 
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