For our GSX concours resto project we need a pit free trans support member # 9796239. [Edit 9796240 68-70 based on Duane's catch infra] As far as I can tell all 68-72 3-4000 series were the same regardless of whether they were turbo 400 auto or manual trans. I show a different part number for 350 cars so I do not think they will serve as a donor.
Jim, I think you took your info from a parts book again. My 70 assembly manual lists 9796240 for a GS 455 coupe 9796239 for all less GS 455 coupe (which would be for a 350 car) There are actually 4 different crossmembers for our cars 350 coupe, 455 coupe, 350 conv, and 455 conv. The diferences are due to the different emergency brake cables, brackets, and bracket placement. I have a perfect 9796239 (350) crossmember from a NC car and may have a 9796240 (455) available, but will need to check. I will get back with you sometime today. Duane
Duane Nope the parts book is correct. I just misread it. I show a # 9796240 to be correct for a 68-70 4 speed 455 car. I am unsure as to whether that number carried over for 71-2. Do you know? In any case thanks for the pick up on the number. I would, like to talk to you if you have what we need. We have a correct one which is structurally sound but it has some pits that would prevent it from being used on this type of resto without a lot of work. I am fishing for a viable alternative.
Duane Nope the parts book is correct. I just misread it. It shows a # 9796240 to be correct for a 68-70 4 speed 400-455 car. I am unsure as to whether that number carried over for 71-2. Do you know? In any case thanks for the pick up on the number. I would like to talk to you if you have what we need. Joe We have a correct one which is structurally sound but it has some pits that would prevent it from being used on this type of resto without a lot of work. I am fishing for a viable, economic alternative. Otherwise I will just have to do the cosmetic work on the one we have.
As near as I can tell, the main difference between the th350 and th400 crossmembers are that the one for the 400's has a slot cut into it that the front brake cable passes through. The 350 cable goes over the crossmember and not through it. The convertible/Sportwagon (68-69) ends are shaped differently as they are bolted to the top of the box frame and not into the frame as on the coupe. At least that is what I noticed when working on my 69 Sportwagon. Mark
Hi Mark Do you have a picture or if not can you point me in the direction of one so that I can see where and how this slot is cut in the support. Thanks Harvey
Jim, Mark is right. I pulled the original (# 9796240) out of my 71 Stage 1 GSX today and matched it up to the 70 350 crossmember. The 2 stampings are identical except for the slot where the front cable goes through, and the part number. If you cut the slot in a 350 (9796239) it would look identical, except for the part number, and that is on the top where you can't see it once installed. The 455 part looks real nice except the ends are a little thin. They are all there, but are thin. (If you want, I can get a repair kit from Mike and fix the ends also.) The 350 part is beautiful and so are the ends. If you are interested in either piece, you have my number so let me know. Mark, The convertible crossmembers are also shorter due to the boxed frames. Duane
Duane, I was going to say they were shorter, but since I never measured them I wasn't 100% sure. Didn't want to get beat up by saying so if it wasnt' correct. ou: Though not correct, the Olds Cutlass crossmembers are really nice as they have the slot cut even on the TH350 units. Guess Olds used only 1 for coupes and 1 for conv. regardless of trans. The added nicety is that they bolt on and don't use the rubber/bracket setup on Buicks. Yes, I know it is not correct for a concours car, but you don't have to worry about the ends rotting away. Would be nice to find a conv or Vista Cruiser one for my 69 wagon. Harvey, I don't have a picture handy and it may take me some time as things are frozen up here at the moment. What I can tell you is that the slot is on the drivers side rear of the crossmember in the area of the "hump" for the exhaust pipe. Mark
Hi Duane, Are you up to posting a picture of the crossmember showing where the slot is?? (Please...pretty please :laugh: ) :Comp: :beer Harvey
Harvey, I noticed you have a couple of 67 GS 400's. The slot should be the same as on them as the cable should go through the crossmember in the same spot on them too. Mark
Harvey, I can't help with a picture, I don't have a digital camera, but if someone was kind enough to send one to a poor manufacturer like me, I sure could use it. Duane Sorry, I couldn't resist.
crossmember stuff You guys are all pretty correct. The big block cars all had the slot cut in it for the emergency brake, the convertible crossmembers are different mostly because they are shorter. The only thing I would add is that Pontiac crossmembers interchange. John Chamberlain
I will have a side by side comparison of the two, maybe tonight. I have one from a 70 GS455 and a 71 Skylark 350. I have had quite a few inquiries on the visual differences so I will get some pics soon. I will post a link here when I am done. And, no the one for the 70 is not for sale. I also think the ones for the 69-72 Grand Prix and 70-2 Monte Carlo maybe the same. I know all 69-72 GP models had the 400 trans and boxed frames. Don't have any in the local yards to verify this but I am going from memory when I stripped a 70 GP last year.
Thanks Duane and you too George for instructive responses on the cross members. Do I understand that the Buick A body cross member respective applications remained the same for 68-72?
