Transmission Grabbing

My first post:
I have a 2010 Tacoma 4WD , 66,413 miles total. Truck has been driven on pavement, 2 miles to work, 2 miles back home 3 days a week. All scheduled maintenence done on time by Toyota (including transmission service at 35,577 miles) except once (by a local garage). Twice a year I took it to the desert in southern Utah on dirt roads, eased it carefully over holes or dips in 4WD. Retired in June, had the truck and transmission serviced at 59,886 miles, and then pulled a U-Haul trailer from Utah to Florida - the harshest thing I have done with the truck. Kept highway speed to 55 and had no issues. Until just after arriving in Florida. Now when I start out in 1st gear the transmission shudders until I get up to 3rd gear. After a couple miles..no problem. If I start the engine and idle for 5 minutes before engaging the transmission...no problem. Fluid levels are full and the clean, no leaks. Haynes manual suggests worn splines, warped pressure plate or flywheel, fatigued diaphram spring, oil on the clutch plate, warped linings or loose rivets.

My questions: Am I looking at a repair issue or a replacement issue? If I let it warm up every time, am I delaying the inevitable or risking a bigger issue? And lastly, how do I go about figuring out which service center (other than a Toyota dealership) is good?

 

Your going to want @gearcruncher to chime in on this.

 

Welcome aboard.

 

Welcome to TW...I’m not a mechanic but I hope you get it figured out!

 

Welcome!

 

Welcome to TW! Someone with mechanical experience should chime in soon.