lq9 pilot bearing
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Teching In
Joined: May 2016
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lq9 pilot bearing hi everyone, im new to the forum so i apologize if this is in the wrong section. I recently bought an 86 c10 with and lq9 and t5. I have the motor and trans out due to bad lifters and i figured id replace a few other things while they are out. Im unsure on what pilot bearing to use. The bearing thats in there is a smaller needle bearing style and from what ive read online i should be using the "larger" bearing. The t5 shaft has been cut down if that makes a difference. any help?
Not sure what was done to your input shaft. This post does list the part number for an LS7 pilot for a T5 trans.
https://ls1tech.com/forums/manual-tr...-can-here.html
https://ls1tech.com/forums/manual-tr...-can-here.html
LQ9 doesn't have the crank flange protruding out of the block. Neither does the 5.3L; it was only found on select early LQ4s mated to the 4L80e. It appears that the "large"/later-style (LS7, late T56 and TR6060) pilot will work based on the above information, but your best bet would be to measure how far the input shaft extends beyond the bellhousing, with any spacers/adapter plates attached. Per the GMPP catalog (20 mm = ~3/4"):
14061685 Pilot Bearing (not shown) Use with manual transmissions if the input shaft extends beyond the bell housing more than 20mm
12557583 Pilot Bearing (not shown) Use with manual transmissions if the input shaft extends beyond the bell housing 5mm or less (or recessed slightly)
12557583 Pilot Bearing (not shown) Use with manual transmissions if the input shaft extends beyond the bell housing 5mm or less (or recessed slightly)
Thread Starter
Teching In
Joined: May 2016
Posts: 3
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so the input shaft of the trans has been cut down and is definitely less than 20mm beyond the bellhousing. It is almost flush with the bellhousing. I have the larger bearing and it looks like if I use it then it will interfere with the splines of the shaft.
The previous owner used the smaller type bearing. Would this setup even work if it was wrong? Im confused as to what is going on here. I have been trying to fix all the hack work that was done on the truck when i got it.
The previous owner used the smaller type bearing. Would this setup even work if it was wrong? Im confused as to what is going on here. I have been trying to fix all the hack work that was done on the truck when i got it.
If it were to interfere with the splines of the shaft, then the trans wouldn't properly bolt up to the engine - there would be a gap even as the bellhousing bolts were tightened. I know from experience.
The smaller bearing would work for a few miles, but the input shaft would be unsupported, and it would eventually tear up the input from the undue stress.
The guidance by the GMPP manual above is your best bet. However, you'll note that there isn't anything about what to use if the input extends between 5 and 20mm (~.200 - .750") beyond the bellhousing because GM didn't offer a trans input in that length. People have successfully spaced the small bearing aft in order to ensure proper engagement of the input shaft snout. If the large bearing doesn't work, you could use spacers to space the small bearing out of the bore up to just under half its width.
The smaller bearing would work for a few miles, but the input shaft would be unsupported, and it would eventually tear up the input from the undue stress.
The guidance by the GMPP manual above is your best bet. However, you'll note that there isn't anything about what to use if the input extends between 5 and 20mm (~.200 - .750") beyond the bellhousing because GM didn't offer a trans input in that length. People have successfully spaced the small bearing aft in order to ensure proper engagement of the input shaft snout. If the large bearing doesn't work, you could use spacers to space the small bearing out of the bore up to just under half its width.
Last edited by hookemdevils22; May 17, 2016 at 11:30 PM.
