what is the gear ratio of a 1978 cutlass


Asked by Apr 22, 2008 at 06:15 PM about the 1978 Oldsmobile Cutlass

Question type: General

what is the gear ratio of a 1978 cutlass

2 Answers


See other post.

1 of 1 people found this helpful.

re: "What is the gear-ratio of a '78 Cutlass?" I'll assume you're talking about the rear differential, not the transmission. Not sure if they(Oldsmobile), marked the "rear-ends" the same way as they did in the mid seventies(73-77). However if they did, you'll need to safely lift the car so the rear axel. assy is about 16" off the ground. You probably dont have to absolutely do this, however since there may be some cleaning/scraping involved it makes this alot simpler. On the passenger side axel tube about 12" away(towards the tire), from the diff. housing there is a axel code stamped on the tube, facing down. It was used by Olds.(GM), in identifying manufacture, build date, ratio. You may have to scrape/brush/clean off a large area to read this, a bright light will help. An "O"(a letter,not a zero, means built by Olds.), is usually the first thing you'll see followed by a build sequence. It goes #1 - Jan., #2 - Feb. and so on. Then a letter, "A" - first week, "B" - second week and so on, so "04C", would be April, 3rd week. Not sure if they put the year of manufacture, if you see an "8" by itself most likely the year.Then a ratio code, not sure about "G" body codes, but "A" body's went something like this: A(A, B, C, D),2.56, 2.73, 2.95, 3.08, so an "A A", would be an 2.56 non-Anti-Spin "open" type diff. and so on. If it has a "C" as the first letter then it is a Anti-Spin(this is what Oldsmobile called its locking differential, and is what most people refer to as a "posi"), followed by a lets say "D", so "C D" would be a 3.08 posi. So the whole sequence may look something like: O04CCD, also look for a small aluminum tag attached to the diff. housing cover(9 o:clock bolt location), it should have the ratio, if its at the 5 o:clock position it may be a "posi" tag.

Your Answer

Oldsmobile Cutlass Experts

  • #1
  • #2
  • #3
View All

Related Models For Sale

Used Chevrolet Monte Carlo
8 Great Deals out of 1,174 listings starting at $1,125
Used Chevrolet Impala
507 Great Deals out of 32,641 listings starting at $1,000
Used Buick Regal
154 Great Deals out of 5,605 listings starting at $2,495
Used Chevrolet Caprice
133 listings starting at $6,995
Used Oldsmobile 442
54 listings
Used Chevrolet Camaro
424 Great Deals out of 31,674 listings starting at $3,495
Used Ford Mustang
340 Great Deals out of 42,823 listings starting at $1,488
Used Cadillac DeVille
1,415 listings starting at $2,000
Used Pontiac Firebird
9 Great Deals out of 695 listings starting at $2,850
Used Dodge Charger
347 Great Deals out of 36,027 listings starting at $1,999
Used Pontiac Grand Prix
14 Great Deals out of 2,492 listings starting at $1,900
Used Dodge Challenger
187 Great Deals out of 26,062 listings starting at $5,999

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.