LS1 vs. LS7 pilot bearing; same or different????????????????
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The LS7 pilot bearing cannot be used. It is the same as the LS2 pilot bearing (LS7). The only thing you can use is the LS7 clutch disc and pressure plate. The LS6 other items have to be used.
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St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
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St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
We talking pilot bearings, or clutch release bearings?
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St. Jude Donor '09-'10-'11
The above numbers are for pilot bearings. The ID's are different too, so the propshaft input spined shaft nose is a different diameter too.
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St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
Then how do you use a C5 driveshaft mated up to a LS7 or 2 crank if your installing an LS7 in a C5? Custom crank? That doesn't sound right. I know the reluctor has to be a 24X piece (if you're keeping the C5 pcm), but this pilot bearing question has me puzzled now.
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Steve, I've been chasing this myself part of the weekend. I was checking parts numbers in AutoZone and there's NO listing for an LS3 equipped cars pilot bearing, but there is for the LS1 and 2 cars. Trying to figure it out.
If the ID's are different, then that would mean that a hybrid bearing would have to be used because of the requirement for the LS1 pilot bearing ID for the c5 Torque Tube input shafts. I don't think this is the case because there's a LOT of guys running around with LS2 and 3 based motors in their cars.
I've got a puller on the way so I'll pull the pilot bearing and see how it fits on the input shaft to the Torque Tube once it's out (It's Tony's GM tool so I should be able to remove in one piece).
If the ID's are different, then that would mean that a hybrid bearing would have to be used because of the requirement for the LS1 pilot bearing ID for the c5 Torque Tube input shafts. I don't think this is the case because there's a LOT of guys running around with LS2 and 3 based motors in their cars.
I've got a puller on the way so I'll pull the pilot bearing and see how it fits on the input shaft to the Torque Tube once it's out (It's Tony's GM tool so I should be able to remove in one piece).
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Ok, found on Tech that the LS3 pilot bearing is a ball bearing type that seats in the area where an auto converter would center itself on the crank. So an LS3 pilot bearing is a definite no use item. The LS2 pilot bearing is looking to be the same given the parts houses I've looked at with pics, looks to be similar/same.
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Steve asked if they were different and he was swapping into a C5. I simply stated you need to use the LS1/LS6 for a C5 application. You cannot use the LS2/LS7 pilot as it will not fit.
Same goes with the throwout bearing (slave cylinder).
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I don't know about the nose not fitting because that looks to be the same size. It's moreso about the placement of the bearing. The LS1/6 bearing rides in the hole in the center of the crankshaft, the LS2/3/7 bearing rides in the outer ring that a TQ convertor would center itself on, and sits farther back than the LS1/6 bearing does.
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They are the same! I have both engines out! But the distance of the pilot bearing is almost an inch farther back on the ls7 than the ls6!
It makes sense that the trque tube is farther back because the ell housing is bigger!
It makes sense that the trque tube is farther back because the ell housing is bigger!
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Due to getting different answers from basically every other person, even GM folks, I bought both just in case. Well... from a person who actually just replaced his pilot bearing on an LS3 in his C5 last weekend...Just like Gene said(
), I ended up using the LS1/LS6 pilot bearing
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Due to getting different answers from basically every other person, even GM folks, I bought both just in case. Well... from a person who actually just replaced his pilot bearing on an LS3 in his C5 last weekend...Just like Gene said(
), I ended up using the LS1/LS6 pilot bearing