1970 TCS Switch at transmission

[Tony H.]

My TCS is not kicking on in 3-4 gear as it should. I am wondering if it may be the TCS switch at the transmission. Is this part number the same for 1970 as for 1971? I saw the 1971 part number posted earlier, GM#3961567. What should this part cost me and where is the best place to get it? (local dealer seams high in price in general)? Is this a part that TLD would be able to get?

Mean while, how do I troubleshoot this system? I guess I will start with the easy part, TCS solenoid at the intake manifold, and test the solenoid for continuity. Beyond this, I'm not sure what to test without my Corvette library at hand which I am temporarily away from. I always keep the DVOM, vacuum pump and some simple hand tools in the car so I can do some simple testing while away from home. Thanks for any help.

[Patrick H.]

Re: 1970 TCS Switch at transmission

Tony,

Does it work in first gear? I know my 71 does, but I don't know if yours should.

It is a small demand part, so I doubt TLD has it, but try them.

I bought an extra from the dealer myself for the 71.

Patrick Hulst

[Joe L.]

Re: 1970 TCS Switch at transmission

Tony----

The 70-71 switch is GM #3961567, as you found. GM list for this switch is about $9. Sometimes, though, if you go to a GM dealer for a few "low buck" parts, they will use their "special price program" on you. This program will often double or triple the "GM List" price of parts under $100, or so. I think that it kind of works on a "sliding scale" in which really low buck parts(like $0.50-5.00) are tripled. As the price goes up, the "multiplication factor" goes down. So, that's why some small parts can seem to be quite expensive. The rationale is that on the sale of a few low buck parts, even at REAL GM list price, there are not many actual DOLLARS to be made. So, the "special price program" kicks in to make the sale worth their effort.


Cranes Corvette

[j. Wright]

Re: 1970 TCS Switch at transmission

Tony- Trans TCS switch is available from ZIP Prods., and can be found in their catalogue. Around $10. J.Wright

[Bill Clupper]

Re: 1970 TCS Switch at transmission

Tony, I'd check the power to the solenoid and the wiring connections first, the switch is simply a spring loaded ball that grounds when it hits a flat spot on the shifter shaft. I've seen some with one flat and some with two. One flat operates in 4th only. two in third and fourth. not much to really go wrong with the switch, but for ten bucks.....?

[Roberto L.]

Re: 1970 TCS Switch at transmission

Zip is offering the 70/71 switch under code ES 475 at the same price ($10). Roberto, NCRS #30019, RMC