Flywheel bolts

[Archive]

My 98 with auto had the flywheel bolts come loose twice. . D/C says have to replace the flywheel as the holes are eqq shaped. About
a $600 fix. Have a Dunn-rite converter and
shift kit with about 50k mi. Anyone else had this problem? Any ideas on cause or fix?
Thks for you help.

 

[Archive]

Two possibilities come to mind: vibration from heavy pulling with converter locked at low rpm; center hole of the flywheel was out of center, causing off-balance of the torque converter (that's what indexes the converter to the crank).

 

[Archive]

Or the bolts weren't properly torqued in the first place. Vibration/movement has enlarged the threaded holes on the crank causeing loose fitting bolts,that caused the bolts to loosen the 2nd time. Might have to tap the crank bolt holes to the next size up. Easy enough to check so that it doesn't happen again with the new flywheel.

 

[Archive]

Thanks for you input guys. . I will check the
concentricity of the flywheel when they get it off and also the threaded holes in the crankshaft. I complained to D/C and they have agreed to cover 50% of the bill so I guess I can't complain.

With regard to pulling heavy loads locked up at low rpm. . I lock out o/d and let the converter lock up when it wants to. I could delay the lock up by keep the throttle open for a longer time but thought it was easier on the transmission to let it lock up around 30 -35
mph. Is this a bad assumption?

 

[Archive]

Jim,the TC should lock up more like 45-50 mph,have the dealer change it while it's in there.

 

[Archive]

TC lockup at 30-35 sounds about right with the OD locked out.


------------------
'95 2500 SLT ClubCab, automatic, 3. 54 LSD

 

[Archive]

Here's the latest on the flywheel bolts.
When the local D/C shop removed the transmission we found four of the six threaded blocks on the converter that the flywheel bolts to had broken off the converter. The breaks were at the welds. It appears that the original installer either failed to torque the bolts properly and/or failed to use lok-tite on them. I still have difficulty understanding why it took a year for them to loosen. Anyway, both D/C and Dun-Rite have agreed to share 50/50 with the fix and I think that's fair. If anyone has any additional comments I would appreciate hearing from them.