AODE lost 4th gear w/o warning

1994 FORD F-150
200 MILES
Avatar
DRIVEBYTRUCKER
  • MEMBER
  • 2 POSTS
'94 5.0 F150 with fresh engine (off road). All emmissions, EEC, EFI, etc. removed/replaced. Now carburetor, with Optishift trans controller.
Trans has always shifted great. While traveling, 4th gear went away, still have 3-4 upshift, but RPMs freewheel in 4th as if there's no line pressure. It will downshift back to 3rd when I slow down. All other gears/reverse are good, just no 4th. Replaced fluid when I replaced the clutch lockup solenoid as part of the Optishift installation. Fluid still smells fresh.
Verified that the new trans contoller is functioning properly.
COuld it be an electrical/mechanical breakdown? A solenoid failure?
Aug 28, 2011 at 3:27 AM
Advertisement
Avatar
HMAC300
  • CERTIFIED EXPERT
  • 48,601 POSTS
have a trans pro look at this, it may be you have a bad seal or burnt a clutch pak up. Or it may be something simpler. although it sounds like an internal trans problem.
Aug 28, 2011 at 1:52 PM
Avatar
DRIVEBYTRUCKER
  • MEMBER
  • 2 POSTS
"sounds like an internal trans problem". Really?
-I'm thinking burned clutches would create scorched smelling fluid, wouldn't it?
-Would a seal failure affect more than high gear? Like maybe reverse and high?
Is there anyone available at this site that has experienced this particular sympton on an AODE?
Aug 29, 2011 at 11:03 AM
Advertisement
Avatar
KHLOW2008
  • CERTIFIED EXPERT
  • 41,814 POSTS
The front clutch is for the OD gear and if it fails, you would not have any 4th speed. Others gears would not be affected. A bad seal is more likely to be the cause and it is internal.

When seals fails, you might not have any burnt smell with the fluids. The only way to confirm is to perform a pressure test on the 4th speed hydraulic circuit.
Aug 29, 2011 at 1:02 PM