I have owned my truck since may 2003 and have noticed a weird thing when the temp is low outside, 30 degree range. It starts and runs fine goes right in gear but when you get out on the raod it seems to run excessive rpm for speed like its not going in to od or converter is not locked. It will hold this rpm and shift pattern for the first 2-3 miles, at highway speed then goes to normal. I rarely drive my truck when its cold out as its a rv puller and see's no daily driving miles. If there is a quirk i would like to document it with the dealer as my warranty will expire in a year and the truck won't have 20,000 on it when it does expire. Also can the dealer firm up the shift pattern. The thing has a nice crisp low second shift but real spongey on the 2-3 and overdrive shift. Its actuallly tacks up between gears instead of a pronounced drop in rpms. I used to help my brother build the old autotrans and slipage was considered bad for tranny life. Any insight would be appreciated. Thanks Sharps-Nut

 

This is normal...... The PCM (I believe) on cold days will hold the engine in gear longer, to help warm the engine and put less stress on the motor, so it won't "Lug" in cold weather.... I have a 97 w/ 4.10 and an at.... notmally shifts into OD w/ locked tc at about 35, on cold days it will wait more rev's and take up to 45 mph before id drops in, normally i drive slow for the first couple of miles, to let her warm up, then she is fine.... hope this answered your question!!

-Robb

 

I Live Less Than A Mile From The Highway, And When Its Cold It Takes My 2001 Psd Longer To Shift, At Least Until She Warms Up, And Then She Runs Just Fine.

 

Yep - it will shift slower 'till it's warmed up, and the TC won't lock until the tranny warms up to a certain temp. Perfectly normal!

As for your shifting - you may want to check into the Sonnax valve and Tri-springs. They are a cheap and fairly simple mod that will firm up your shifts and help your tranny live longer. I kinda doubt that your dealer will do anything to firm them up.

 

Thanks for the information. I figured it was a device causing the slow shifts. Its the only new truck I plan on buying for the next 10 plus years and I am wanting to to ake sure if there a re any problems I get it taken care of before warranty expires. The highway is right in front of my house so this explains the lack of lock up. I always baby the heck out of it until the temp comes up, well really I baby heck out of it most all the time. Is the kit a internal shift kit like we would have put in the c-6 transmisssions or more difficult? Thanks for the information. Sharps

 

The sonnax valve and tricummulator springs replaces the valve and either adds to existing springs or replaces them. All in the accumulator valve body. This mod worked real well on my 2002 f350. It is fairly simple to do but gets a little messy with all of the ATF everywhere. It requires dropping the tranny pan and unbolting the accumulator valve body, the rest of the work you can do on the bench.

 

One thing that I do here in Alaska is when it's cold out, after startup and during warmup, I put the tranny in neutral, this lets the tranny fluid circulate and warm up. This is done before I take it out on the road and put a load on it. We often get temps. down to -40, usually when its that cold I try to minimize any startups.

 

I think I will do the modification on that trans after the warranty is up. I should not put to much wear on it before then and I don't want to fight with uncle henry if the thing goes **** up and has any mods. psdinalaska, Thanks for the alaskan tip. I usually let it idle a while before take off but not in nuetral. Sharps-Nut