Hi,

I have searched this board for information on decoding a 700R4, found a couple of links from 3-12 year old posts that are no longer valid.

I have a code: 1DBM220B, which is a 91, 700R4, mfg Thursday 08/08/91, on the first shift. Apparently, the "DB" identifies what it originally came in, does anyone know what that is? Or any chart available to look it up?

Thanks!!

 

You have the Julian-Date Correct.

That Unit should be from a Cadillac Brougham with a Chevrolet SBC 5.0L/ 5.7L Engine.

 

I am guessing that was not what you had hoped for??

Those Cadillac THM700-R4 Cores were decent... NOT Great... but decent.

 

Hey Vortec,

I have my 700R4 out to rebuild (with Dana's help) and just scraped clean my code 9FKM351C. From another thread where VIN derivative is mentioned do you know this is someplace else on the case I haven't found yet?

Thanks!

 

What area of the Transmission did you scrape clean... that removed the Broadcast Code?

THM700-R4 Units will normally have the Serial Number/ Broadcast Code Stamped into the Oil-Pan Rail:

 

To be clear, I did not remove the code, I scraped clean the area of junk at the pan rail to FIND the code I wrote. There are no other codes or VIN-derivatives stamped into my 700 now that I have completely cleaned it. I misunderstood and thought there was.

 

Thanks for that info, sorry for the almost 2 year gap, I think I found a chart somewhere, & never checked back here. Have since forgotten & am back to re-research it. The core is decent, has been rebuilt twice since I've had it. This last time we beefed it up with 5-pinion planetary, ala 4L65, & a billet input drum, among other upgrades. This is in a 1 ton truck with a 402BB, we fried the 3-4 clutch first trip, partly due to an aftermarket electric fan sensor failure. Beefed the THM700-R4, & reverted to a clutch fan. Even towing up steep grades, temp gauge didn't budge.