My 95 k2500 ld is having temp. related issues. it works fine for the first 3-5 miles then it will shift to 4th and lock up at 10mph. I'm pretty shure its the temp senser inside the trans that is causing it. I would like to find a trans part place in minnesota to buy the parts from. I plan on replacing the solonids and manifold pressure switch and tcc solonoid as long as i'm in there. Otherwise somewhere in the midwest to save shipping costs. I don't want to go to mr goodshaft and pay 3-5 times as much. Thanks in advance.

most trans shops will sell you the parts at close to cost, at least the ones i have gone to here in wi do

I was hoping to bypass them and buy direct fro their scorse in minneapolis but can't seem to find one on line or in the yellow pages. I found a place in alabama[bulk transmission parts] that has all the components but i prefer to buy locally in case all the parts aren't right. I hate paying shipping to send back wrong parts and the delay. I have used parts but i don't want to do it twice.

When i was looking for those last year, i got some from flea-bay, but would up going to my local dealer for the solinoids. They were actually cheaper than anywhere else, much to my amazement. Might call them and see what they say.
Don

I try to shy away from the stealers.$5bolts,$75+ oil cooler lines that leak ect. I'd sooner pay a little more somewhere else and deal with knowlable people. Maybe someday they will realize why the aftermarket is flourishing and their loosing business.Most dealerships know little to nothing about these trucks. Just replace engine ,injection pump or transmission.[makes them big bucks because of rate book or should i say shaft book]Thats how they try to sell new cars because it costs so much to have them fix older ones.They charged me over $1000 to replace a engine rpm sensor on my 91 6.2. Over $350 labor for a ten minute job. I'm still stingin from that one.

I am curious as to why you believe the trans fluid temp is causing it. Make sure your fluid viscosity is correct. "right transmission fluid"
you need pressure to go through the 1-2 shifting solenoid.
and you need pressure to go through the 2-3 shifting solenoid to reach the Torque Conver clutch Solenoid. "TCC" Solenoid for short. Once this happens then The lockup will occur through this route.
Now the Pump has a control valve that opens and allows Line pressure to lockup the torque converter. This valve is controlled by the TCC solenoid valve which is the "signal" for the main valve at the pump.

Your TCC Valve Bore is more than likely worn and leaking and needs to be reamed and a new valve reinstalled
The fluid heats up and gets thinner. Leaks past the TCC valve and "signals the control valve to lockup.

it is very common for transmission shops to overlook this fault.

That would be the sonax shure cure? I have the posting on the 6.5 engine forum also.I finnally checked for codes and it has:27 glow plug relay fault,35inj.pulse width error,57 pcm 5 volt shorted,and 85 undefined ratio error. I will be getting it in my shop as soon as i get done parting out my 91. I'll spend some time with the ohm meter checking wires and connections. The transmission was working great before a 100 mile pull of 10,000 lbs in 4wd in a snow storm. I am unsure of how many miles on transmission. The truck has 275,000 miles. It had a snow plow on it when i bought it. I'll post what i find out with the ohm meter.