Spencer_P

Good afternoon all, I'm hoping someone can point me to a set of tri-metal .001" undersize crankshaft bearings for a 99 4.0. I've found individual bearings but not a set that includes the thrust bearing. The undersize crank bearings should be all I need to start reassembling the 4.0 I opened up months ago planning to just do a reseal.

BruceB

might try

https://www.summitracing.com/parts/s...okee/year/1999

Saudade

Did you really mean .001 and not .010 ?

.010" undersize are also on rockauto.

Spencer_P

Yes, .001".
I've checked Summit, Rockauto, Amazon, and google.

5-Speed

What was the part number again? I am a dealer for Mahle/Clevite so I can check inventory levels from the factory.

Saudade

You can find part numbers here if you need them.

https://www.moparpartsgiant.com/part...agram=00i92787

Get the numbers for the .001 and search on the part numbers.

Looks like #16 and #19 are the .001' undersize.

Spencer_P

83507086 Bearing-Crankshaft Thrust
83507080 Bearing-Crankshaft
These are the OEM PNs but I'm not sure that does you any good in searching Mahle/Clevite products. I haven't found a listing for .001" undersize Mahle/Clevite to give that specific PN. I'll try checking their website.
83507080 brings up a couple active listings but nothing current as far as a thrust bearing.

EDIT: Mahle's website does not list .001" bearings for the 4.0L

5-Speed

I am coming up with about the same results as you. Found 3 main bearings but you need 6. Everything else is either on never ending BO or just says discontinued. Even Crown doesnt offer a .001 bearing.

bluejeep2001

Its your engine , and you can build it as perfect as you want, But it seems like a lot of time spent to gain .001 tolerance on only the bottom bearing caps. I would be surprised if that .001 was accurately manufactured as compared to standards. If i recall, you wanted to run standard bearings on the block side of the mains and the .001 on the caps? When you plastigauged the journals, were you within the recommended .0025 limit? If you want that accuracy, might be easier and faster to get the crank miked, and have them turn it to .001 smaller than a set of .010 under bearings

Spencer_P

At this point, I can't even remember if I plastigaged the main bearings.
I think between amazon, eBay, and summit I've found enough bearing sets to do them all correctly except #5 thrust bearing. But according to my measurements #5 needs .001" on upper and lower bearings so if I put standard in I'd imagine #5 won't be very happy and buying all these sets of bearings isn't cheap.
I've thought about having the crank turned as well, I was trying to avoid that cost but that may be what has to happen...

bluejeep2001

Not questioning any of your measurements, but consider this...if .001 makes or breaks your motor....then there would not be millions of jeeps out there with upwards of 200k on them..all stock and unrebuilt.