700R4 TCI HD Servo

[wpdozer]

I just ordered a TCI HD servo, Part# 890-376003. TCI claims it will iliminate 2-3 "flair", Whatever that means. I assume It will tighten up the 2-3 shift time. My trans slides into 3rd under "aggresive" throttle, or when going up an incline. It only does this from the 2-3 shift, 1-2 and 3-4 are firm, but I have to back off the throttle to allow it to hook up from 2-3. If I don't it slips. Once it hooks up I can get back into it with no sliping. I Installed a 16 pass Derale fan driven trans cooler horizontally under the flatbed after the trans had a soup to nuts HD rebuilt. It runs cool enough to be able to place the palm of my hand on the pan, so overheating is not the problem. So the question is- Will this servo remedy some of the irratic behavior prone to this transmisson? I really don't like this trans at all. HELP!

[Edahall]

So the question is- Will this servo remedy some of the irratic behavior prone to this transmisson? I really don't like this trans at all. HELP!

Yes it may remedy the erratic (shift flare) behavior you described. But make sure your TV cable is set up tight enough. What year 700R4 is in your truck? The 1987 and newer 700R4's were much improved. The original 1982 700R4 in my Suburban had the same symptoms as you described and it literally exploded about a week after I installed exhaust headers for more power so I ended up installing a newer 700R4. I'm like you, I don't like this transmission. That's why everything except this Suburban has been converted to manual transmission (NV4500 or NV5600).

[wpdozer]

[QUOTE=Edahall;290352]Yes it may remedy the erratic (shift flare) behavior you described. But make sure your TV cable is set up tight enough. Well, You were right on the money with that one! The trans is an 82 original that was installed by the previous owner. A junkyard find that was out of a Jeep. He installed it as is, no rebuild, if you could amagine that! It was probably out of a wagoneer or cherokee gasser 360-401. It didn't take long for the 6.2-banks turbo, to burn it up. I had it rebuilt to the tune of $1800. I pulled it and reinstalled it so it was all parts and labor. It had a brand new TV cable so I left it as is. I had two new TV cables in stock for a rainy day for the 6.2-700R4. Today was the day, aparently that new TV cable prev owner installed was for the Jeep setup, Much longer than my GM cables when I compaired them. I installed the shorter GM cable this morning and got throw your head back shifts out of it. Still going to install the servo, Can't hurt right? Big thanks for your feedback. Wayne

[convert2diesel]

[QUOTE=wpdozer;290353I installed the shorter GM cable this morning and got throw your head back shifts out of it. Still going to install the servo, Can't hurt right? Big thanks for your feedback. Wayne[/QUOTE]

Careful Wayne. Even with all the go-fast bits in the tranny, the 700 series trannys shouldn't shift that hard. Line pressure is too high. In the original problem you didn't have enough tension on the cable. Now you have too much. Just as distructive. Loosen it off a couple of clicks at a time till you get positive but not dramatic shifts at the correct speeds.

This job is best done with a pressure gauge hooked up to the pressure port (1/8th pipe fitting) located on the upper part of the tranny just behind the bell housing on the drivers side. Don't remember the the numbers for the 700 but your local tranny shop could do this in 15 minutes.

Good luck

Bill

[wpdozer]

Ok, After some investigation, my trans could not have come from a Jeep, AMC only used the TH400 for a few years. so that was BS on the part of the previous owner. That being said, I made the TV cable adj sugested by convert2diesel. two adjustments with a test drive after each adj. The shifts softend up but are firm and positve. Shift points are as follows-In MPH with GPS nav. 1/2-12/14. 2/3-27/30. 3/4-45/50. I made three runs of light, moderate and heavy throttle. Do these numbers sound right or should I make more adjustments? Before I replaced the cable, the shifts were way too early as compared to now and the turbo is performing far better than before.