Need part number for transmission switch

[Mark A.]

Hi Guys,
Could someone give me the part number for the transmission switch used on the CEC system for my 71 LT-1? Thanks, Mark

[David L.]

Re: Need part number for transmission switch

Mark,

The part # for the T.S.C. (Transmission Smog Control) switch (mounts on transmission) for the 1971 Corvette w/4-speed M.T. is 3961567 (Group # 4.075). The same switch is used in my 1970 Camaro SS350 w/4-Speed and other 1970-1971 Chevrolet models w/4-Speed.

I assume your car has a 4-Speed M.T., if not, let me know and I will look again in my 1970, 1971, and 1972 Chev. & Corvette parts catalogs.

Dave

[Mark A.]

Re: Need part number for transmission switch

Mark,

The part # for the T.S.C. (Transmission Smog Control) switch (mounts on transmission) for the 1971 Corvette w/4-speed M.T. is 3961567 (Group # 4.075). The same switch is used in my 1970 Camaro SS350 w/4-Speed and other 1970-1971 Chevrolet models w/4-Speed.

I assume your car has a 4-Speed M.T., if not, let me know and I will look again in my 1970, 1971, and 1972 Chev. & Corvette parts catalogs.

Dave

Yes, the LT-1's are 4 speeds. Thank you Dave, for the info. Mark

[Terry M.]

Re: Need part number for transmission switch

Mark,

The part # for the T.S.C. (Transmission Smog Control) switch (mounts on transmission) for the 1971 Corvette w/4-speed M.T. is 3961567 (Group # 4.075). The same switch is used in my 1970 Camaro SS350 w/4-Speed and other 1970-1971 Chevrolet models w/4-Speed.

I assume your car has a 4-Speed M.T., if not, let me know and I will look again in my 1970, 1971, and 1972 Chev. & Corvette parts catalogs.

Dave

Rather interesting Dave that the same part number switch shows for MT for Corvette 1970 to 1972 because the configuration of the 1970 Corvette switch is different than 1971 & 1972. My 1970 AIM UPC 7 sheet B6 shows 3961567 for the switch, however the same page in the 1972 AIM shows 3996286 for the switch. I do not have a 1971 AIM handy (which is why I did not respond sooner), but I would expect the number in the 1971 AIM to be the same as the 1972 number since the configuration was the same. I expect you are seeing the effect of SERVICE PART consolidation in the parts books. All you folks who love NOS parts should keep this example in mind as the fruitlessness of your boasting, and remember it is only one of many examples.

BTW in this case the configuration difference effects the functionality of the part, so this is a case where the SERVICE PART will not install without further modification to 1971 and 1972 Corvettes. This configuration difference IS spelled out in the TIM&JG since it is easily judged by the Chassis judges.

Mark, if you have a very early built 1971 it is possible it uses the 1970 switch. I have not personally researched the break point for the change of the switch configuration, but others may have.

[David L.]

Re: Need part number for transmission switch

Terry,

My 1972 Corvette Parts Catalog (Sept. 1971) lists switch # 3961567 for 70-71 Corvettes.

My 1981 Corvette Parts Catalog lists switch # 3961567 for 70-71 Corvettes and switch # 3996286 for 72-74 Corvettes.

If you read my previous post more carefully I never stated that the 3961567 was for the 72 Corvette. However, I did state that I do have a 1972 Corvette Parts Catalog.


Dave

[Joe L.]

Re: Need part number for transmission switch

Rather interesting Dave that the same part number switch shows for MT for Corvette 1970 to 1972 because the configuration of the 1970 Corvette switch is different than 1971 & 1972. My 1970 AIM UPC 7 sheet B6 shows 3961567 for the switch, however the same page in the 1972 AIM shows 3996286 for the switch. I do not have a 1971 AIM handy (which is why I did not respond sooner), but I would expect the number in the 1971 AIM to be the same as the 1972 number since the configuration was the same. I expect you are seeing the effect of SERVICE PART consolidation in the parts books. All you folks who love NOS parts should keep this example in mind as the fruitlessness of your boasting, and remember it is only one of many examples.

BTW in this case the configuration difference effects the functionality of the part, so this is a case where the SERVICE PART will not install without further modification to 1971 and 1972 Corvettes. This configuration difference IS spelled out in the TIM&JG since it is easily judged by the Chassis judges.

Mark, if you have a very early built 1971 it is possible it uses the 1970 switch. I have not personally researched the break point for the change of the switch configuration, but others may have.

Terry------


There's no mystery here and no SERVICE parts consolidation issue, either. The GM #3961567 switch was used for 1970-71 Corvettes (as well as other non-Corvette applications). The GM #3996286 was used for 1972-74 Corvettes (as well as other non-Corvette applications). Yes, those switches are markedly different, are not functionally interchangeable (without changing other parts), and neither one ever superceded the other for SERVICE. As far as I know, there was no significant difference in the configuration of either switch over the long availability span of both switches which just concluded relatively recently when both switches were discontinued without supercession.

I also doubt that there was any model year "overlap" with one or the other switch in PRODUCTION. That's because to use either switch on a non-cataloged model year application would have involved changes in other parts.

By the way, I could have posted pictures of both switches but in doing so it now appears to me that would be interpreted as my somehow "boasting". No matter as it saves me (and my back) a lot of trouble in trying to dig them out.

[Terry M.]

Re: Need part number for transmission switch

Terry,

My 1972 Corvette Parts Catalog (Sept. 1971) lists switch # 3961567 for 70-71 Corvettes.

My 1981 Corvette Parts Catalog lists switch # 3961567 for 70-71 Corvettes and switch # 3996286 for 72-74 Corvettes.

If you read my previous post more carefully I never stated that the 3961567 was for the 72 Corvette. However, I did state that I do have a 1972 Corvette Parts Catalog.


Dave

Terry------


There's no mystery here and no SERVICE parts consolidation issue, either. The GM #3961567 switch was used for 1970-71 Corvettes (as well as other non-Corvette applications). The GM #3996286 was used for 1972-74 Corvettes (as well as other non-Corvette applications). Yes, those switches are markedly different, are not functionally interchangeable (without changing other parts), and neither one ever superceded the other for SERVICE. As far as I know, there was no significant difference in the configuration of either switch over the long availability span of both switches which just concluded relatively recently when both switches were discontinued without supercession.

I also doubt that there was any model year "overlap" with one or the other switch in PRODUCTION. That's because to use either switch on a non-cataloged model year application would have involved changes in other parts.

By the way, I could have posted pictures of both switches but in doing so it now appears to me that would be interpreted as my somehow "boasting". No matter as it saves me (and my back) a lot of trouble in trying to dig them out.

I am the one with egg on my face or foot in my mouth -- take your pick and add the crow.

A) I failed to read Dave's post thoroughly, and misread his Camaro application information for Corvette information.

B) The 1971 AIM on UPC7 sheet B6 shows part number 3961567 for the transmission mounted TCS switch, just as Dave's parts books show.

C) I was wrong when I stated that 1970 was different. As Dave's parts books show 1970 & 1971 were the same and 1972 was different, just as Joe confirmed.

Joe, my shot about NOS parts was directed at the many Corvette advertisements we see or auctions that state "restored with NOS parts." It was also intended as a warning to the many who fall for that BS. You are correct there is no parts consolidation here. I will have to remove this one from my list of FAILS. No need for a picture. The TIM&JG explains the configuration differences, and now I will have to look it up (I was hoping to avoid that) to see if the years it calls out are more accurate than my memory.