Highest (lowest numerical) rear gears you've seen?

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Originally Posted By: 440Magnum
The lowest I've personally seen were civilian 80s Chrysler M-bodies (Diplomat / Gran Fury / 5th Avenue) that were something like 2.26:1. Chrysler didn't have a rear-drive 4-speed (O/D) transmission at that time and in the Iacocca years there was exactly no budget for any new rear-drive tech, so they developed the A999 version of the A904 3-speed. It had a "deep" (higher numerical ratio) FIRST gear so that they could put a 2.26 rear end out back, effectively turning 3rd (direct) into a pseudo-overdrive and using convertor slip and the deep first gear to keep the cars from being complete and total pigs off the line (they were still painfully slow). But that setup could return mid to high-20s MPG in a fullsize 3-box v8 sedan with a very reliable 3-speed automatic setup and a brutally strong ring/pinion set- I've seen a lot of them with over 200,000 miles and no transmission work at all (a far cry from Chrysler front-drive automatics of just a couple years later!) So it was making the best of a bad situation. The cop-spec M-bodies could be had with that same deep first gear and a 3.23 rear end, which actually made them launch surprisingly fast for only ~150 horsepower.


Some had the same gearz WITHOUT the deep gear in the trans. In a r000lb St. Regis. Putt...putt...
 
Originally Posted By: SubieRubyRoo
2006 Odyssey has like a 4.46 final drive, a little higher than Subaru's 4.44. It's the highest I've seen.


The Renegade is also up there with crazy low gearing. The 6 speed manual in 1st gear is just as low geared as the "trailhawk" model in low range.

Originally Posted By: FlyNavyP3
Lowest gears in a commercially purchased vehicle (non medium or heavy duty) I've worked on was my Grandfathers old Dodge 1972 W300 225 Slant 6 Granny Gear 4sp Dana 70 F/R with 7.17 gears. It would pull absolutely anything. Just not fast.


Wow! I bet that had a top speed of 40! I bet you could pull anything up a hill without giving it any gas!

Originally Posted By: TiredTrucker
Originally Posted By: SEMI_287
My 93 Z28 auto had a 2.73 and my 300C has 2.82. A 2.29 is ridiculous!


Think that is ridiculous? Try that the commercial heavy truck drive axle OEM's are now offering 2.28 ratios in axles rated for 40,000 lb to be put on commercial semi trucks. I have 2.64 Meritor diffs in my semi truck. I just looked up on the Meritor axle website and saw they are offering 2.28 now. Lowest I had seen before was 2.47. Those 2.28's obviously are being offered for those that are buying into the major engine down speeding concept. Some of those setups have 13L engines only turning 1100 RPM under full 80,000 lb load. Wouldn't work at all for what I use a commercial truck for. I'll leave that kind of nonsense to idiots who sit in cubicles and spec fleet trucks and don't even know how to drive them across the parking lot, let alone with 46,000 lb in the trailer and dealing with major grades.


But >1500 lb/ft of torque at off idle, 10 speed transmission and a 10,12:1 first gear.
 
I don't think anyone beats my '84 Olds Cutlass: 2.14:1 from the factory. Yes, 2.14, not 2.41. More here:

http://www.442.com/oldsfaq/ofdif.htm

I replaced it with a posi-traction axle out of a Grand Prix. It was labeled to be 2.41:1, but it measured out at 2.29:1.

My '87 Regal had the TH-200-4R transmission, and came with the optional 3.08:1 rear end. It made the 307 pretty peppy.
 
Well when you have 2.14, I guess you're not in trouble should you have transmission problems and be stuck with only 1st and 2nd gear. That thing must have been cruising at 1000RPM n the highway.

Even the Jeep 4.0L which is supposed to be big on low end torque doesn't feel right with 3.07 gears and factory sized tires.
 
Originally Posted By: Jarlaxle
Originally Posted By: 440Magnum
The lowest I've personally seen were civilian 80s Chrysler M-bodies (Diplomat / Gran Fury / 5th Avenue) that were something like 2.26:1. Chrysler didn't have a rear-drive 4-speed (O/D) transmission at that time and in the Iacocca years there was exactly no budget for any new rear-drive tech, so they developed the A999 version of the A904 3-speed. It had a "deep" (higher numerical ratio) FIRST gear so that they could put a 2.26 rear end out back, effectively turning 3rd (direct) into a pseudo-overdrive and using convertor slip and the deep first gear to keep the cars from being complete and total pigs off the line (they were still painfully slow). But that setup could return mid to high-20s MPG in a fullsize 3-box v8 sedan with a very reliable 3-speed automatic setup and a brutally strong ring/pinion set- I've seen a lot of them with over 200,000 miles and no transmission work at all (a far cry from Chrysler front-drive automatics of just a couple years later!) So it was making the best of a bad situation. The cop-spec M-bodies could be had with that same deep first gear and a 3.23 rear end, which actually made them launch surprisingly fast for only ~150 horsepower.


Some had the same gearz WITHOUT the deep gear in the trans. In a r000lb St. Regis. Putt...putt...


Yep. A998 transmission... the 80s were just awful for car guys.
 
Surprised nobody has mentioned this, but the current Dodge Hellcat cars with automatics have a 2.62 rear end, which is just way off the charts for most modern vehicles with tires on 20-inch rims. But that's how you get a 300 mph top speed, and the 8-speed automatic they use with the Hellcat has a 12.34:1 low ratio. Combined that with blower-induced off-idle torque, and the tall rear end isn't a problem- in fact, any higher (numerical) rear end would just smoke the tires even more than it already does.
 
Originally Posted By: Miller88
Well when you have 2.14, I guess you're not in trouble should you have transmission problems and be stuck with only 1st and 2nd gear. That thing must have been cruising at 1000RPM n the highway.


To the contrary, it had the 3-speed automatic (1:1 third gear), 25" tall 205/70R14 tires, and 70 mph was 2,000 rpm. With the wind noise of that old Cutlass (T-tops), the engine speed, exhaust noise, etc...it was a loud ride at speed.

As a more modern baseline, our MDX has a 0.53:1 5th gear, an axle ratio of 4.375:1, 29" tall tires, and an engine speed of 1,881 rpm at 70 mph.
 
Originally Posted By: 440Magnum
Surprised nobody has mentioned this, but the current Dodge Hellcat cars with automatics have a 2.62 rear end, which is just way off the charts for most modern vehicles with tires on 20-inch rims. But that's how you get a 300 mph top speed, and the 8-speed automatic they use with the Hellcat has a 12.34:1 low ratio. Combined that with blower-induced off-idle torque, and the tall rear end isn't a problem- in fact, any higher (numerical) rear end would just smoke the tires even more than it already does.



X2, Boosted V8's love tall gearing, My old '50 Studebaker Pick-Up with a Magnacharged LS1/4L60E had a 3.00:1 Ford 9-Inch, Progressively went up from a 3.70:1. The Truck got better traction & pulled harder with the 3.00's
 
Originally Posted By: Hokiefyd
Originally Posted By: Miller88
Well when you have 2.14, I guess you're not in trouble should you have transmission problems and be stuck with only 1st and 2nd gear. That thing must have been cruising at 1000RPM n the highway.


To the contrary, it had the 3-speed automatic (1:1 third gear), 25" tall 205/70R14 tires, and 70 mph was 2,000 rpm. With the wind noise of that old Cutlass (T-tops), the engine speed, exhaust noise, etc...it was a loud ride at speed.

As a more modern baseline, our MDX has a 0.53:1 5th gear, an axle ratio of 4.375:1, 29" tall tires, and an engine speed of 1,881 rpm at 70 mph.



TH200-C is what you had.
 
Originally Posted By: clinebarger
TH200-C is what you had.


Correct. Complete with the sticky TCC solenoid and reverse gear that went out at 100k miles or so, requiring a rebuild.
smile.gif
 
Originally Posted By: SubieRubyRoo
2006 Odyssey has like a 4.46 final drive, a little higher than Subaru's 4.44. It's the highest I've seen.

My 2003 5spd Tracker has 5.12 diffs, and a fairly low 1st, but they didn't go crazy with the transfer case low range so it has only the same crawl ratio as a normal jeep YJ. On the road 60mph is something like 2700-2800rpm.
 
The highest gear ratio I've personally owned was 2.77.

1973 Dodge Charger SE Brougham with 400 4 barrel, 727 Torqueflite. The original rear end had been torn up and replaced with a 9.25" rear end from a Fury police cruiser / interceptor.

It was no quarter mile runner but had great top end; wonderful highway cruiser that passed when you wanted to pass someone and got about 13 MPG while lookin' sharp.
 
Overall gearing in my Camaro is 3.42 differential ratio with 0.5 6th gear ratio = 1.71.
Works fine at speeds over 65 mph cruising on the highway. But top speed is achieved in 5th gear.
 
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