LW = 2.93 ratio posi B = Buick build source 04 = Built January 4th 2 = second shift I do not think the rear codes give the year or at least these do not.
No question what you say is correct. I looked at it up to 70 which was a 2.93. If I had switched books to include 72, it would have shown that same code was also used as the performance posi 3.42 option in 1972.
Thanks guys - my car is a '72 Stage 4-speed. It was built the first week of March. I was checking the date codes on all my parts. The rear is one item I was not sure of. Looks like it checks out to be correct. Mike
Thanks guys - my car is a '72 Stage 4-speed. It was built the first week of March. I was checking the date codes on all my parts. The rear is one item I was not sure of. Looks like it checks out to be correct. Mike
Now I see the source of the confusion. The way he typed it LW [space ]B was read as the two letter code LW for a 8.2 , 2.93 literally as written. B after the space was interpreted as B for buick under the rear end code convention which is correct. He did not type "LWB" which is the the three letter code for a 71 or 72 posi with a 3.42 ratio. So I would not agree that "LW" without the B atached is the identifier for a 72 3.42 posi. And to further confuse the matter I do not think the year of the axle housing was used. So as typed I would say the answer I gave is correct . Clearly for a known 72 rear [ and I did not pay attention to his logo] you would ask where is the third letter in the sequence.
The GSXtra had an article once as well that said many of the 71/72 rear diffs had just "LW" not the complete "LWB". I believe it was May/June 2002 and my 71 Stage 1 has exactly that. LW 234 2, the 234 works out to be about 2 weeks before car was built...3.42 posi. Nothing is ever easy with these old cars!! :laugh:
You are right thereaas the dealer books call them them LWB for 72. But maybe the assembly manual is different .
another 2 cents Parts is parts and books are books.......... everybody is correct. LWB or LW B, the first to digits are the axle ratio and the third is the axle build source. For 455: 1970- LW = 2.93, TH400 Std. 1971 -LW(B) = 3.42. 4spd Std. w/posi. or TH400 w/performance axle w/posi. Stage 1, Std. with 4spd. or TH400 w/posi. 1972 - LW(B), = 3.42, 4spd Std. w/posi. or TH400 w/performance axle w/posi. Stage 1 , Std. with 4spd or TH400 w/posi. as written in 3 Buick Source books, Parts,Service and Build. Date: May 15,1970 Service Bulletin 70-I-91 Approximately 300 1970 Skylark,Gran Sport,SportWagons to be built in Flint beginning May 10,1970 will be equipped with 1971 Rear Axle Assemblies. LWB = 3.42 w/P.T. - GS455,Stage 1, 4spd and TH400. LHB = 3.42 - GS455, Stage 1 , 4spd and TH400. Parts is parts and Books are Books.
Lots of input guys, Thanks. I think I'll snap a pic and post it. Now Jim - what would the correct carb # be for a '72 Stage w/manual trans? Everyone knows that the auto shift #s end with even number and the manual cars end with an odd number. I cannot find what the number should be for a '72 manual car. Or does anyone out there have a '72 manual car that has the correct carb? Thanks again -Mike
Hey Mike, does you car have the rally gauges?? BTW, 7042243 seems to be the correct carb for stage 1 4 speed...there is a reference to another number but it might be a typo.
My '72 chassis manual states... 7042242 (49 State) 7042942 (California) Same carb # for TH400/Muncie 7042243 is for a non-stage 455 4-speed.
7042242 is stage 1 auto from everything I see (parts book, chassis manual and makes sense, my 71 auto is 7041242). Brett S here on the board has done lots of research and 7042243 looks pretty happy, but once again some of the different sources have conflicts (parts book lists that as non stage manual tranny carb and 7042942 as stage 1 manual but parts books can't always be trusted as they do get updated). Chassis manual list same 7042942 as stage 1 calif only, no mention of tranny. Don't have carbs in my assy manual. There have been lots of threads on here so some searching might show up some other info. Could be the manual cars got the same carb stage 1 or not? 72 is one of those years where everything seems to be screwed up as lots of changes going on throughout the year....and nobody has done much research in their frenzy to get the 70's.... I think I finally have the 72 seat belt info sorted out too, had to get a copy of the actual legislation...ugh...reading that crap will make your eyes fall out..
