Have Transmission Questions? Ask a Mechanic for Answers ASAP
Sounds like your truck has morning sickness. It's when the seals in the transmission don't seal as well as they used to, and the pressure bleeds past them. After the transmission and fluid warms up a little, the seals get softer and seal better, allowing the pressure necessary to properly operate the transmission. You could try getting a transmission fluid flush and see if it helps any
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You didn't have to open a new question to reply to me. You can reply right here. The difference of the trans fluid temperature in the summer time versus the winter time is trivial compared to the temperature of the fluid after driving the truck. vehicles with "morning sickness" have it in the summer and in the winter. It does not go away in the summer simply because of the outside temperature is warmer. If you feel hot transmission fluid you would know what I am talking about. It gets very hot. When it does, those old worn out seals will get soft and seal much better. If you would like though, I can definitely opt out and let somebody else have a shot at it
Welcome I'm Chris aka Moose
The previous tech has opted out and will no longer be helping.
Have you ever started the truck and let it idle about 30 seconds prior to shifting to D or R to see if the issue does not occur?
Is it the 1-2 shift that will not complete?
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I am in my upper 30's, have a wife and 2 sons. I farm, fish, hunt, build, and coach youth soccer. I work on anything with an engine, been to many schools and classes through my 12 years with the dealership to get trained and certified. I try the best I can to share what I know and or have access to with my customers. Please consider I base my questions and answers to you, solely on the information you give me since I am not there to see, smell, hear, touch, or test. I try my best to be here everyday starting at 3pm central. Rating an answer is required. Please let me know if your not pleased prior to rating or if you cannot rate me so I can try to help a different way. God Bless and have a great day.
I really hate that you came to Just Answer, paid to get an answer, but appears like you left not happy nor pleased with my help. I am still here available to help more. We can start over or just pick up where we left off. Let me know what I can do, so you will be pleased with my assistance.