CK5
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'84 K5 gearing question
- Thread starter kent-k
- Start date
What axles?
I believe it's the original 10 bolt.
I figured it was 2.73, but when I lifted the truck and spun the wheel, I got about 2 driveshaft rotations
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Once upon a time, I had an ‘80 K10 that came with 2.73’s so they’re always possible.
I know GM offered a 2.56 in 2wd trucks but I’m not sure if they were available in a 4wd.
I know GM offered a 2.56 in 2wd trucks but I’m not sure if they were available in a 4wd.
I may be wrong, but I thought that there was a ratio higher than 2:73. I thought that there was a 2.36, but not positive.
I know that there was a 2.29 available for the car 7.5 ten bolt.
I have a 2:73 ten bolt rear axle in my 81 G-10 van,it had 3:08's but the original diff ate the side gear housing area and I had to replace it..
I have seen a K5 that had 2:73's factory,an 80's model with a 700R4..
Never saw 2:56's in a truck 10 bolt ,but there may have been an option for them...had a 10 bolt in an El-Camino that had a 2:56 posi..the poor 267 V8 could barely spin the tires on sand!..but it would cruise at 80 mph at a fast idle and get 20 mpg..
I have seen a K5 that had 2:73's factory,an 80's model with a 700R4..
Never saw 2:56's in a truck 10 bolt ,but there may have been an option for them...had a 10 bolt in an El-Camino that had a 2:56 posi..the poor 267 V8 could barely spin the tires on sand!..but it would cruise at 80 mph at a fast idle and get 20 mpg..
Yup, but I am not sure that actually reflects what was actually available from the factory, or actually installed.
Pulling the cover off and finding the numbers is the best.
84 and 85 did come with 2.73, I have one here and I know of a few out there.
To simplify, year and drivetrain governed what axle ratios were available/used.
By the time the trucks were around, there was little, if any option for gearing, although fleet sales may have been a different story. GVWR, engine/trans combo, CA or not CA, all impacted what ratios were used, not customer choice.
You couldn't walk into the dealer in 1985 and order a K5 with 4.10's.
Now, what dealers might have been willing to do in their service shop could be a different story.
By the time the trucks were around, there was little, if any option for gearing, although fleet sales may have been a different story. GVWR, engine/trans combo, CA or not CA, all impacted what ratios were used, not customer choice.
You couldn't walk into the dealer in 1985 and order a K5 with 4.10's.
Now, what dealers might have been willing to do in their service shop could be a different story.
Looking at the 84 brochures the GMC Jimmy is the only brochure that shows gear ratio. 273 was standard with the 305, 308 for the 6.2
Mine came with 3.08.
funderburgh22
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My 82' k5 had a 2.73 12 bolt in it, not positive if that was stock to my truck though
My 85 with the 305 came with 3.08s.
