69 chevy trans swap ?

[jwtrucking69]

ok guy here goes i swap my turbo 350 for another turbo 350 out of an 82 chevy van i thought they were the same but after i pulled the old i noticed the new one had two set of wires coming out of the case i have no idea what these are for {thinking torque converter lockup? nuetral safety?} i have no idea to be honest but i swapped them anyway and now when the truck is shifted to drive it wont shift at all just tries to take off in drive not
1st but if i drop into first and manually shift it its does great im totally lost i also have yet to hook up the kickdown linkage it wasnt as long as the one that came out of the truck any ideas appreciated i have no knowledge of auto trans. thanks

[kwmech]

Sure it's a 350? 82 was the first year for the 700. If a 350 the wires are for convertor lockup.

[krue]

Could be a turbo 350c which has a lockup converter. Don't know much about them, so I'm no help there.

[lilpup69chevy]

nope its not a 700 at all what you got is what they call a th350 c its basically a 350 turbo with a lockup converter 81 was the last year for the regular th350 my 85 silverado had this transmission, you can upgrade it and it will work however nothing th350 wise will work for it in the line of rebuild kits or shift kits you would be smart to use the lockup convertor and wire the lockup switch b&m offers a kit for this or i'm sure you could do it yourself still a decent transmission but i'd rather have the old th350 hope that helps you

[jwtrucking69]

ok i agree the trans has the lockup converter now but any suggestions why it takes off in drive instead of 1st unless you manually downshift it?

[lilpup69chevy]

well maybe the vacuum modulator??? i doubt it would have anything to do with the detent cable and i assume it coming out of a van it wouldn't have a manual valve body so i'd check the line to the vaccum modulator and look for a leak maybe might even change modulator, i don't think having the lockup unhooked will have any affect on the shifting no reason to

[Longhorn Man]

the mod wouldn't do that.

[Green Machine]

Sounds like a stuck governor to me.

[VetteVet]

I'm not convinced that you have a th350c as you might have a 700r4 or a 2004r. 82 was the first year for the 700r4. The easiest way to tell is to look at the bottom of the transmission pan and match it to one of these on this website.
http://www.maliburacing.com/auto_tranny_id.htm

[lilpup69chevy]

yeah but i would assume that the van he got it from only had the 1 2 D selector on the column instead of one that said 1 2 3 OD, another way is that he is driving it and the R4 has a different tailshaft length and i'd assume he would have had to modify a driveshaft to ran the R4 and not the th350c as its the same length

[Americanrider]

Tranny ID chart form the Hurst shifter website:

http://go.mrgasket.com/pdf/trans_id.pdf

[Longhorn Man]

Actually a TH 350C would be longer than a correct TH350 from on of our trucks. All of ours have short shafts, and after the mid 70's (maybe even 73) they were all long shafts, so some shaft mods are still needed.

[lilpup69chevy]

well my 1981 chevy has a short shaft th350 in it and always has. but i didn't know that all 67-72 had short shaft th350's, but actually that is helpful to me so thanks for the info longhorn man

[Longhorn Man]

an 81 had a short shat... good to know. Thanks.
But yeah, these all had short shaft Th350's.