overdrive Posted September 5, 2009 Share Posted September 5, 2009 I've not found a build sheet yet for my 70 SS, and the car has a 71 454 engine, so I can't prove that it's an original SS by those 2 methods. I've always been sure it's an SS, since the car has the correct unrestored suspension parts for an SS and the Level Ride system lines and control valve are still in place and in unrestored condition. It's obvious they have been there since new and are undisturbed. To get to my point of this post, I'm rebuilding the TH400 trans and it has an ID tag riveted to the pass side that IDs the trans as built in 70 and it has the code CR. The drvr side of trans has the serial # stamped on it and it matches the VIN, so the trans is definitely the original. I got a book today to help me to do this rebuild, by Ron Sessions, and he included pages listing the codes on the tags for all of the TH400s. These pages and codes identify what kind of car the trans was originally installed in and the size of the motor that it was bolted to at the factory. The CR on mine was only used behind 454s. All 454 Montes in 70 and 71 were Super Sports and since my trans serial # matches the VIN, I have some more proof that it's a true SS and without a build sheet, so far. I just thought some of you here would be interested in this info. I haven't ever read anywhere before that so much info was available about the origin of a trans. Link to comment Share on other sites More sharing options...
Andy's Auto Posted September 5, 2009 Share Posted September 5, 2009 Too cool duder. And it rules out an original 402 as well. Not finding a buildsheet sucks. That POS 402 72 I just bought has dual sport mirrors but no way to see what the RPO code to see if you could in fact get them. Either way, they are going on Project Richey, the orange 72 I bought off GRat. Good work, Detective Overdrive. Link to comment Share on other sites More sharing options...
Sam (Bones) Posted September 5, 2009 Share Posted September 5, 2009 I knew you could do this, it's hard to find the info to decode trans tags can you get the tags codes from him??? it would be a great addition to our tech page here Link to comment Share on other sites More sharing options...
overdrive Posted September 5, 2009 Author Share Posted September 5, 2009 Quote: it would be a great addition to our tech page here It's all in my book. It's called How to Work with and Modify the Turbo Hydramatic 400 transmission. It has the codes for all GM makes and models. I can send the information to someone, after I finish this rebuild. Link to comment Share on other sites More sharing options...
footballubet Posted September 5, 2009 Share Posted September 5, 2009 Good info to have. Glad you confirmed your suspicions. Hope you'll be able to get the tag code info for us. Link to comment Share on other sites More sharing options...
RichG Posted September 5, 2009 Share Posted September 5, 2009 According to the restoration packet sent out for 1970 monte by GM, there are 5 trans codes. RR= 3speed manual, WA= 4 speed manual, VO= Powerglide, GS= TH350, CR= TH400. In the restoration document the specs for the TH400 are the same for an LS-3 and LS-5. It would seem according to info that GM put out that the TH400 was the same for a 402 & 454. Sorry. Link to comment Share on other sites More sharing options...
overdrive Posted September 6, 2009 Author Share Posted September 6, 2009 The book I have shows that GM made the 400 available to other manufacturers. They were used by AM General, Avanti, Excalibur, Holden, Jaguar, Jeep, Revcon Motor Home, Rolls-Royce and Volvo Truck as well as by every GM division. This book has all of the codes and there are more than 5 pages. It shows that in 70, the 400 had 5 different codes when used behind 454s depending on the HP rating and/or the Model of the car it was installed in. CB, CR, CG, CS & CY. The 402 cars had different trans codes than these. To get some more information, would some of you that have 70 Montes w/402s that still have the original trans please check the code on it? We need to know if it is CR or not. This could be interesting. Please help! Link to comment Share on other sites More sharing options...
cudax Posted September 6, 2009 Share Posted September 6, 2009 My 70 is an original 402 car and I am currently running the original 400 in it with a code of "CD". Mike Link to comment Share on other sites More sharing options...
overdrive Posted September 6, 2009 Author Share Posted September 6, 2009 Thanks Mike! That's one code that my book shows for a 402. I would think all of the other 70 Montes with 402s had the same code as yours. The other codes listed in the book under 402 will probably be for the other Chevy models. The book is out in the garage right now and it's bedtime. Anybody else? Link to comment Share on other sites More sharing options...
monte70car Posted September 6, 2009 Share Posted September 6, 2009 I have a 78 Suburban 400 trans that has the id plate on the passenger side with cr on it. Looking in my Chevorlet SS Muscle Car Red Book they only show the m40(400th) no difference rather it went behind a 402 with 325hp or the 454 with 450hp. and I can get a picture of the 78 trans as it in the back of the El Camino. Link to comment Share on other sites More sharing options...
overdrive Posted September 7, 2009 Author Share Posted September 7, 2009 That looks like CP, not CR. Mikes code shows there are different trans codes for 402s and 454s in the 70 Monte. His is the original trans and so is mine. Mine has CR and his has CD. Link to comment Share on other sites More sharing options...
CrazyDavey Posted September 7, 2009 Share Posted September 7, 2009 me thinks this is going to one of those, was there ever a '72 SS that got out the door, was there ever a convert, was there ever a LS-6 car???? Who knows what happened 40 years ago, if you knew somone and had connections you could get the factories to do some strange things. I knew a guy the ordered a '70 SS with special paint, I don't remember what the GM color was called but it was the most brillant yellow I've ever seen on a Monte and I've never seen another one like it. Back then the factories didn't think twice about substituting parts if they were out of what was supposed to go in. To them a th400 was a th400, the difference between the engineers and the manufacturing groups. While the intention might have been to have a specific item go with a specific car I can guarantee you it didn't always happen. So Dan I think you have probably come across something that should work but won't always, it won't replace a buildsheet. Your car has plenty of clues that it's legit but it won't qualify as "documentation"....JMO.... Link to comment Share on other sites More sharing options...
overdrive Posted September 7, 2009 Author Share Posted September 7, 2009 If we can simply look at the codes, as Mike has done, on 70 Montes with 402s and TH400s and SS cars that have original transmissions, we can have absolute proof as to what the codes actually are, not what someones papers or books show. I'm not too interested in build sheet proof for my car. I know what it is and don't have any intentions of selling it. I'm just interested in finding out if the GM restoration packet is correct or maybe it's the GM provided chart reprinted in the rebuild book that's correct. So far, it looks like the book is accurate. The tag has the year and the trans code both on it. The tag that Robert shows also has the year. Link to comment Share on other sites More sharing options...
Jared Richey Posted September 7, 2009 Share Posted September 7, 2009 This is great information, its good to have some kind of proof that your car is the real deal, heck nowadays a build sheet doesn't meen as much, with the aging tricks people can do on a peice of paper. Actual numbers means a lot! And Andy I'm anxious to see pics of project Richey. Its gonna be sweet you're done with it. Link to comment Share on other sites More sharing options...
overdrive Posted December 6, 2009 Author Share Posted December 6, 2009 Another post got me digging into trans codes again. I've seen that some build sheets have the trans code near the bottom on the right side. It should also be in box 28, near the top of the sheet on the left side. Does anyone here have a build sheet for a 70 Monte with a 402 and automatic? If so, please tell us what the code for the trans is. CR, CD, or something else? Thanks for any help on this. Link to comment Share on other sites More sharing options...
monte70car Posted December 6, 2009 Share Posted December 6, 2009 I'm looking at a build sheet I got off of ebay when I was putting my sheet back together. box 28 looks to be crhf and its a 454 Monte sheet. Mine the only part of box 28 i have is the last letters which is cc. I know my was a turbo jet 400 with a 350th and a 12 bolt 2.73 peg leg. what I would like to see is a 70 saddle build sheet I have part of a 70 sheet that I pulled from my backseat and it listes the steering col. color dk sad box 71, box 72 tach has 938 Link to comment Share on other sites More sharing options...
72-CLASSIC_RIDE Posted December 6, 2009 Share Posted December 6, 2009 Not a 1970 model year but my 72 has the 400 w/ CD code and is a 402. Link to comment Share on other sites More sharing options...
Andy's Auto Posted December 6, 2009 Share Posted December 6, 2009 As I sit here looking at both a 70 402 build sheet and a 70 L65 build sheet, cockroachs ate both. But I do have a mint 71 SS454 buildsheet in my office. News at 11. Hunny Bunny knows if I take her grocery shopping we will stop at the shop this morning. Box 28 of the 350 car is legible. GS. Link to comment Share on other sites More sharing options...
overdrive Posted December 6, 2009 Author Share Posted December 6, 2009 Quote: my 72 has the 400 w/ CD code and is a 402. That matches what the book shows. It shows CD for all 3 years w/a 402. Andy, this book doesn't have any info for a TH350. Robert, I have a 70 sheet that is in great shape and from a dark saddle car. What information do you need? Link to comment Share on other sites More sharing options...
Andy's Auto Posted December 6, 2009 Share Posted December 6, 2009 Just got back with the 71 SS buildsheet. Trans box is 27 and the code is CF. Boy do I want this car. Link to comment Share on other sites More sharing options...
monte70car Posted December 6, 2009 Share Posted December 6, 2009 Quote: Robert, I have a 70 sheet that is in great shape and from a dark saddle car. What information do you need? what does box 71 list for the steering col color? I find it hard to believe it would be dr saddle when dk saddle wasn't a 70 color on sadle was. Link to comment Share on other sites More sharing options...
overdrive Posted December 6, 2009 Author Share Posted December 6, 2009 Quote: Boy do I want this car. I'll bet! Yes, the build sheet layout is a little different after 70. I have a copy of Capri's 71 SS454 sheet and it matches yours, and the book shows CF was only used behind a 454 for 71 and 72. Link to comment Share on other sites More sharing options...
overdrive Posted December 6, 2009 Author Share Posted December 6, 2009 Quote: dark saddle wasn't a 70 color, only saddle was. Robert, are you sure about that? Box 71 is DKSAD. Interior color, or trim in box 43, is 769. This is the same as the trim # on my 70 SS cowl tag. Link to comment Share on other sites More sharing options...
monte70car Posted December 6, 2009 Share Posted December 6, 2009 Th Muscle Car red book has saddle listed but only for vinyl buckets 789. When i ordered my door panels two years again I had to get them custom made as dark saddle isn't listed for 70. the restor packet has 769 as saddle but in vinyl, also in the restor packet it shows the interior trim to be medium saddle and the pillar moldings being dark saddle. My cars inc book shows only light saddle which is 789. Now you say your Monte has 769 which going by the packet says its vinyl and buckets is that right? This is my dark saddle interior Link to comment Share on other sites More sharing options...
overdrive Posted December 6, 2009 Author Share Posted December 6, 2009 Yes, it has vinyl buckets that are faded. What is the correct color? I can look at the places that are hidden from the sun and not faded, but I don't know what the correct name for my original vinyl seat covers is. Link to comment Share on other sites More sharing options...
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