Cold start shifting problems

Hello Tacoma owners, Erich here, new to the Forum and just bought a 2000 Tacoma TRD with a six banger and 5spd manual. So far, the truck is stock except for 5100 Billsteins front and rear, TRD cat back exhaust, and custom grill. It has 153,000 miles. The seller "forgot" to tell me about one issue with the truck. On cold start up, with temperatures down in the mid 40's (and colder, I'm assuming) it absolutely will not shift into any gear, except for 2nd, and that is not easy. I let the engine warm up for about 5min and have to drive for about 1/2 mile or so, in 2nd gear, before it will let me start shifting normally. Maybe its just me (but I dont think so), but also it is sometimes difficult to shift into 1st. The shifter seems to get caught up on something, and does not glide into position smoothly. It doesnt "glide smoothly" into any of the gears, in fact, but especially 1st. ( I have about 20k miles driving experience with a manual trans) I checked the hyd. clutch fluid level and it was a little low, but looked clean. I topped it off with Dot 3, but the problem remains. Any advise on what the problem could be and/or what to check??? Also, any recommendations on best brand of gear oil to use in trans and transfercase??? (Please include why, based on your own experiences) Any good advice would be appreciated ! Thanks for reading and thanks in advance for responding.

 

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