Why does transmission shift hard when warming up in a 98 Cadillac Catera?

Answer 1

COPIED FROM LINK AND USER

STEVEHOGAN

http://www.cadillacforums.com/forums/Cadillac-catera-cimarron-forum/34617-transmission-shift-little-rough.html

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Here's what GM has to say about cold shifting in the Catera:

Document ID# 773783
1998 Cadillac Catera Info - Cold Shift Pattern (Normal Condition) #01-07-30-001 - (01/16/2001)

Cold Shift Pattern (Normal Condition) 1997-2001 Cadillac Catera

with Hydra-matic 4L30-E (RPO ML4)

Some owners of the above vehicles may comment on increased or higher engine speeds when the vehicle is driven immediately from a cold start. The Transmission Control Module (TCM) software contains a function that modifies shift speed speeds when the engine is cold. When activated, this feature will delay the shifts 10 to 15 km/h (6 to 9 mph), depending on the throttle angle.

The cold shift pattern enables if all of the following conditions exist:

• The engine has been running for 5 seconds.
• The engine temperature is between -40°C and +30°C (-40°F and +86°F).
• Vehicle speed is 0 km/h (0 mph).

The cold shift pattern is disabled under any of the following conditions:

• 60 seconds after activation.
• If throttle angle exceeds 60.5 percent.
• Vehicle speed exceeds 50 km/h (30 mph).

This is a normal condition, no repair should be attempted.

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So unless you are experiencing something significantly different that described in this bulletin, there is nothing wrong. Hope this helps.