4l80e dowel hole smaller than the 6.0 block dowel

johnnunez29

Greasemonkey
May 9, 2022
238
49
28
Wouldn’t the surface of the trans and engine be what determines if anything is wrong? Both items inside spin. I’d guess Aslong as both are aligned should be no issue
 

ck80

Moderator
Moderator
Supporting Member
Feb 18, 2014
5,706
9,037
113
If you want the absolute best solution, make good friends with a machinist and have them make you a custom set that is a deparate diameter on each end.
 
  • Like
Reactions: 2 users

johnnunez29

Greasemonkey
May 9, 2022
238
49
28
Opening up the hole in the Transmission is the best bet here. I would do that.
Just got the 5/8 ream. Was looking at .622 reams but not sure how long that’ll take to arrive. I’ll call Monday. But .0030 on the 5/8 (.6250) don’t think it’s THAT much off
 

78Delta88

Royal Smart Person
Supporting Member
May 23, 2022
1,183
1
904
113
SW Arizona
The dowel is an alignment aid on the factory floor at production speed. Bigger concern is the bell housing is correct for the engine and the bolt holes align. The centering is done by the torque converter matting with the back of the crank with correct run out tolerance. Axial centering is the input stator and impeller meshing properly to the stator support and input shaft and the Torque converter meshed properly to the transmission front pump. Then the bolts in proper alignment and torqued to spec. The dowels are just an alignment aid for initial install on the production line and of course later on in the event of R & R.

You could sand down the dowels or remove... But why? Aluminum is softer. Just drill the holes so that hole I.D. matches dowel O.D.
 
  • Like
Reactions: 3 users

johnnunez29

Greasemonkey
May 9, 2022
238
49
28
The dowel is an alignment aid on the factory floor at production speed. Bigger concern is the bell housing is correct for the engine and the bolt holes align. The centering is done by the torque converter matting with the back of the crank with correct run out tolerance. Axial centering is the input stator and impeller meshing properly to the stator support and input shaft and the Torque converter meshed properly to the transmission front pump. Then the bolts in proper alignment and torqued to spec. The dowels are just an alignment aid for initial install on the production line and of course later on in the event of R & R.

You could sand down the dowels or remove... But why? Aluminum is softer. Just drill the holes so that hole I.D. matches dowel O.D.
thank you all. Got it all mated up. reamed the holes a little (Went smooth this time) and attached 6 bolts through bell housing to engine and tightened to 25 pds. Between the TC and FP there was very little over 3/16 gap so i added a thin washer between them , then was able to get a 1/8 bit inbetween easy but no 3/16. loctite and torqued those bolts to 50pds (per circle d recommendation). Now this is all obviously going in a g body i know there is mention of some "ears" that should be chopped of the transmission, i have an idea what that may mean but would much rather be for certain before i take a sawzall to the bell housing. Any one have an image for these "ears"? TIA
 

GBodyForum is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to amazon.com. Amazon, the Amazon logo, AmazonSupply, and the AmazonSupply logo are trademarks of Amazon.com, Inc. or its affiliates.

Please support GBodyForum Sponsors

Classic Truck Consoles Dixie Restoration Depot UMI Performance

Contact [email protected] for info on becoming a sponsor