o/d problem...please help me out here!!

A good tune or chip should stop this from happening, since its electronically controled, and by computer programming, you can technically over ride this. It shouldn't be shifting into o/d though if you've cut the o/d band off, via the o/d button/switch. I'de give superchips tuning a call, and see what they tell you.

BTW, its not a good idea to be racing this thing with it shifting into o/d at wide open throttle. Thats a good way to blow your over drive band.

Dont forget a Tranny cooler.

if that doesnt work, post this on www.tccoa.com

stonegod85 said:

...snip... i just want my o/d to stay off when i want it too.....

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Are you sure it's shifting into o/d or are you feeling the converter locking up? It definately shouldn't be going into o/d if you've got it buttoned off, somethings broke. If it's the converter locking up a tuner can turn it off but I wouldn't.

Another unfortunate Transgo customer! GO read the the J- Mod article at www.tccoa.com. I do not know how many threads I have read how the TRansgo has shelled the trans. They work for awhile and then the 4th gear band gets screwed up. It is something to do with the way Transgo goes about trying to play with the Electronics and they should not. They will overide but normally shift higher into 4th. Mine is at about 5600. I have 3.73's in my 97 and with less mods ran a 14.7. Your shift problems are causing havoc with your times.

Get it out of their before you have to buy a new Tranny. I have 50k on my Jmod a dnit works great. Do the Jmod!

I have to agree. The Trans-go shift kit is probably causing your transmission problems.

The J-mod shouldn't be much more difficult to do, in fact, you can read all the steps to it yourself over at www.tccoa.com in their tech articles for the 4r70w transmission.

You'll need the newer style rubber bonded accumulator pistons, since you have a 97 transmission. I forget the part number for these, but Jerry has them mentioned in his tech articles for the 4r70w transmission at TCCOA. You'll also need two new valve body gaskets IF you need to disassemble the valve body and do more drilling or remove certain parts the Trans-go shift kit required you to install. Also, you'll probably need to re-adjust your line pressure via the Pressure control solenoid IF you adjusted it when installing the Trans-go shift kit. You'll also need a new upper 1-2 accumulator spring. You shouldn't re-install any spring in the lower portion of the 1-2 accumulator piston, and no springs should be re-installed in the 2-3 accumulator piston, it will operate and shift fine without any. If you've put any blocker rings on either of the accumulator pistons, that would be the time to remove them. They're not a good idea to begin with.

Little Tip: Expect to get a transmission fluid shower when doing this. So, be forewarned. You'll also probably need a bottle jack when compressing the 1-2 accumulator piston in order to remove the snap ring. It's a PITA, I know, I've removed one before. You'll need a good set of snap ring pliars, else, you won't get it out. You might also need some petroleum jelly to put the 1-2 accumulator piston back in place, because its a tight fit.

Contact Randy Stinchcomb, and tell him you have a 97GT, and are wanting to upgrade the Jerry mod shift kit. Remember, you'll need the blue upper 1-2 accumulator spring, Newer style rubber bonded accumulator pistons for both the 1-2 and 2-3 accumulators, and probably 2 new valve body gaskets, just in case if you need to take the valve body apart.

After you do all of this, if the problems still persist, I don't know what to tell you other than to keep calling Superchips and see if you can't get a hold of Jerry, as he works for them.

Lentech transmissions, as well as other companies like Performance Automatic makes valve bodies that are 4r70w compatible, and has the holes for line pressure feed already enlarged. The question is are you willing to pay the 250-350(perhaps more) for one ? As far as I know(and unfortunately) no one sells pre-drilled seperator plates for the 4r70w valve body, or I'de tell you to go with them. If you're worried you'll screw drilling the valve body up, then its probably best that you don't do it. If you know anyone that has a drill press and has drilling experience, I'de let them do it, or just dig deep and get a high performance valve body.

stonegod85 said:

so what you're saying is those aftermarket valvebodies are basically the same as the one i have, just with everything already done to them making it a bolt on?

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Yeah, basically.

stonegod85 said:

if that's the case i'll just buy everything to do the j-mod and upgrade the tranny as much as possible that way. correct me if i'm wrong.

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In order to do the J-mod, just carefully read the articles over at www.tccoa.com on the J-mod in the tech articles for the 4r70w transmission. If you need anymore help, I'm willing to help. I've done the j-mod myself, so I kinda got experience in this department.

stonegod85:

The 3-4 shift can only be prevented by changing the program in the PCM (i.e.--a custom tune or a handheld flasher). The shift schedule must be modified so that the 3-4 shift occurs at 130 mph and 8000 rpm. You need both because a shift is commanded on vehicle speed or engine speed, whichever occurs first.

You can reverse the TransGo (filling in holes with brass -- see the TCCoA.com site where "Transmissions 101" is and find the article for hole-filling) and then do the J-mod.

I fear that your OD band is burnt and now must be replaced. It doesn't take too many WOT 3-4 shifts to fry the band. Luckily, it is not too bad to replace.

HTH,

Chris

If he has to replace his o/d band, why not just upgrade to a stronger one ? I think Bauman Engineering sells one for under 200 dollars. Probably not much more expensive than a replacement stocker.