Engine/Transmission (1998.5 - 2002) Lockup question

[MAngelotti]

Let me start by saying that I always noticed my tc lockup slightly over 40 mph on the speedo. Today on my way home after about 30 min of driving I noticed that all of a sudden the tc was not locking up until almost 50 mph. Is this a sign of anything about to happen? What may be causing this? I know that it is locking and staying locked as it should just alot later now. just too noticeable a difference to go unquestioned for me. Any help would be appreciated.



99' 2500,qcsb,4x4, airdog 100, quad xzt+, s&b intake,boost elbow, black

 

[Huff N Puff]

Lock up usually occurs

Let me start by saying that I always noticed my tc lockup slightly over 40 mph on the speedo. Today on my way home after about 30 min of driving I noticed that all of a sudden the tc was not locking up until almost 50 mph. Is this a sign of anything about to happen? What may be causing this? I know that it is locking and staying locked as it should just alot later now. just too noticeable a difference to go unquestioned for me. Any help would be appreciated.



99' 2500,qcsb,4x4, airdog 100, quad xzt+, s&b intake,boost elbow, black

At 35mph. OD occurs at 45mph to 50 mph PCM has an adaptive program and can change shift points. The throttle valve cable can get stuck and change shift points also. A fueling box can alter inputs therefore altering shift points.

 

[MAngelotti]

I added the quad about two months ago and no change until today. I will check the cable. I do remember my 12v would not hit od/lockup until 50mph like clockwork. This 99 has always shifted at 40-43 mph. Strange, I'll see what happens in the morning.

Thanks