2003 LS430 - Taller Ring and Pinion Set
01-09-15, 07:57 PM
#1
Lead Lap
Thread Starter
2003 LS430 - Taller Ring and Pinion Set
Hello,
Has anyone replaced the ring and pinion in the differential with a taller gear set? If so, what ring and pinion brand did you use and what axle ratio do you go up to. I think stock is 3.77:1.
Thanks!
Has anyone replaced the ring and pinion in the differential with a taller gear set? If so, what ring and pinion brand did you use and what axle ratio do you go up to. I think stock is 3.77:1.
Thanks!
01-09-15, 11:22 PM
#2
Pole Position
I've asked this before - and as far as I can tell there's no consensus on what to do.
Basically, all the 90s RWD Toyotas have the same differential gears. The differentials themselves are a little different. For instance, the ISs and the 1990-1997 LS400s have unique differential housings.
The Supras, SCs, GSs, and 1998-2006 LSs have the same differential pointing points. Although they use different sizes of plates between the drive shaft and differential. And I think the LS has a unique thing.
The 2001-2003 LS430s (and 1998+ LS400s, GS4*s) had the lowest final drive ratio out of any of these cars: 3.266.
The GS460 and LS460 have a 2.937 rear end, and as far as I know, that's the tallest gear in a RWD Toyota sedan. Perhaps the tallest rear end of any Toyota car in the last 30 years.
It might be possible that the rear differential from the 460's bolt in to our 430s. But I don't know for certain nor does anyone. And it is more likely that the pinion and gear set swap over.
So the GS430 and the LS430 share differentials when the two have the same transmissions. The 2001-2003 LS430s have the same differentials as the 5 speed GS430s and I believe that the 2004+ LS430s have the same differentials as the 2004-2007 GS430s.
Here's where it gets interesting:
The part view of the2007 GS430 shows the carrier body is the exact same as the 2008 GS460 's rear differential.
It's conceivable that the 2.937 differential bolts into the 2001-2003 LS430s, but it's not certain. I'd bet dollars to doughnuts that you can swap the pinion and gear set. I wouldn't try it though because I'd hate to mess something up and lose use of my car until I got it fixed.
It'd be dumb to run the tall rear diff on the 2004+ LS430s because the taller final drive will cause the torque converter to slip more and it's a Pain in the tuchas to change the fluid in the sealed 6 speed. Whereas there's really no penalty to slipping the 5 speed, you can just do a drain and fill on the transmission once per year. Not to mention the top gear of the 2004+ is already super low - they could probably put in a 2001-2003 differential if they wanted to drop the revs.
Some rough, back of the envelope calculations suggest this could decrease freeway fuel consumption by 7-10%.
If anyone ever pursues it, please let us know!
Basically, all the 90s RWD Toyotas have the same differential gears. The differentials themselves are a little different. For instance, the ISs and the 1990-1997 LS400s have unique differential housings.
The Supras, SCs, GSs, and 1998-2006 LSs have the same differential pointing points. Although they use different sizes of plates between the drive shaft and differential. And I think the LS has a unique thing.
The 2001-2003 LS430s (and 1998+ LS400s, GS4*s) had the lowest final drive ratio out of any of these cars: 3.266.
The GS460 and LS460 have a 2.937 rear end, and as far as I know, that's the tallest gear in a RWD Toyota sedan. Perhaps the tallest rear end of any Toyota car in the last 30 years.
It might be possible that the rear differential from the 460's bolt in to our 430s. But I don't know for certain nor does anyone. And it is more likely that the pinion and gear set swap over.
So the GS430 and the LS430 share differentials when the two have the same transmissions. The 2001-2003 LS430s have the same differentials as the 5 speed GS430s and I believe that the 2004+ LS430s have the same differentials as the 2004-2007 GS430s.
Here's where it gets interesting:
The part view of the2007 GS430 shows the carrier body is the exact same as the 2008 GS460 's rear differential.
It's conceivable that the 2.937 differential bolts into the 2001-2003 LS430s, but it's not certain. I'd bet dollars to doughnuts that you can swap the pinion and gear set. I wouldn't try it though because I'd hate to mess something up and lose use of my car until I got it fixed.
It'd be dumb to run the tall rear diff on the 2004+ LS430s because the taller final drive will cause the torque converter to slip more and it's a Pain in the tuchas to change the fluid in the sealed 6 speed. Whereas there's really no penalty to slipping the 5 speed, you can just do a drain and fill on the transmission once per year. Not to mention the top gear of the 2004+ is already super low - they could probably put in a 2001-2003 differential if they wanted to drop the revs.
Some rough, back of the envelope calculations suggest this could decrease freeway fuel consumption by 7-10%.
If anyone ever pursues it, please let us know!
01-11-15, 10:12 AM
#3
Lead Lap
Thread Starter
I've asked this before - and as far as I can tell there's no consensus on what to do.
Basically, all the 90s RWD Toyotas have the same differential gears. The differentials themselves are a little different. For instance, the ISs and the 1990-1997 LS400s have unique differential housings.
The Supras, SCs, GSs, and 1998-2006 LSs have the same differential pointing points. Although they use different sizes of plates between the drive shaft and differential. And I think the LS has a unique thing.
The 2001-2003 LS430s (and 1998+ LS400s, GS4*s) had the lowest final drive ratio out of any of these cars: 3.266.
The GS460 and LS460 have a 2.937 rear end, and as far as I know, that's the tallest gear in a RWD Toyota sedan. Perhaps the tallest rear end of any Toyota car in the last 30 years.
It might be possible that the rear differential from the 460's bolt in to our 430s. But I don't know for certain nor does anyone. And it is more likely that the pinion and gear set swap over.
So the GS430 and the LS430 share differentials when the two have the same transmissions. The 2001-2003 LS430s have the same differentials as the 5 speed GS430s and I believe that the 2004+ LS430s have the same differentials as the 2004-2007 GS430s.
Here's where it gets interesting:
The part view of the2007 GS430 shows the carrier body is the exact same as the 2008 GS460 's rear differential.
It's conceivable that the 2.937 differential bolts into the 2001-2003 LS430s, but it's not certain. I'd bet dollars to doughnuts that you can swap the pinion and gear set. I wouldn't try it though because I'd hate to mess something up and lose use of my car until I got it fixed.
It'd be dumb to run the tall rear diff on the 2004+ LS430s because the taller final drive will cause the torque converter to slip more and it's a Pain in the tuchas to change the fluid in the sealed 6 speed. Whereas there's really no penalty to slipping the 5 speed, you can just do a drain and fill on the transmission once per year. Not to mention the top gear of the 2004+ is already super low - they could probably put in a 2001-2003 differential if they wanted to drop the revs.
Some rough, back of the envelope calculations suggest this could decrease freeway fuel consumption by 7-10%.
If anyone ever pursues it, please let us know!
Basically, all the 90s RWD Toyotas have the same differential gears. The differentials themselves are a little different. For instance, the ISs and the 1990-1997 LS400s have unique differential housings.
The Supras, SCs, GSs, and 1998-2006 LSs have the same differential pointing points. Although they use different sizes of plates between the drive shaft and differential. And I think the LS has a unique thing.
The 2001-2003 LS430s (and 1998+ LS400s, GS4*s) had the lowest final drive ratio out of any of these cars: 3.266.
The GS460 and LS460 have a 2.937 rear end, and as far as I know, that's the tallest gear in a RWD Toyota sedan. Perhaps the tallest rear end of any Toyota car in the last 30 years.
It might be possible that the rear differential from the 460's bolt in to our 430s. But I don't know for certain nor does anyone. And it is more likely that the pinion and gear set swap over.
So the GS430 and the LS430 share differentials when the two have the same transmissions. The 2001-2003 LS430s have the same differentials as the 5 speed GS430s and I believe that the 2004+ LS430s have the same differentials as the 2004-2007 GS430s.
Here's where it gets interesting:
The part view of the2007 GS430 shows the carrier body is the exact same as the 2008 GS460 's rear differential.
It's conceivable that the 2.937 differential bolts into the 2001-2003 LS430s, but it's not certain. I'd bet dollars to doughnuts that you can swap the pinion and gear set. I wouldn't try it though because I'd hate to mess something up and lose use of my car until I got it fixed.
It'd be dumb to run the tall rear diff on the 2004+ LS430s because the taller final drive will cause the torque converter to slip more and it's a Pain in the tuchas to change the fluid in the sealed 6 speed. Whereas there's really no penalty to slipping the 5 speed, you can just do a drain and fill on the transmission once per year. Not to mention the top gear of the 2004+ is already super low - they could probably put in a 2001-2003 differential if they wanted to drop the revs.
Some rough, back of the envelope calculations suggest this could decrease freeway fuel consumption by 7-10%.
If anyone ever pursues it, please let us know!
They do this in muscle cars and pickups all the time.
Just wondering if there's a gear set for this car. I believe the 2001-2003 cars are an open diff so it should be relatively simple for a shop. However not a lot of these cars were made so maybe the demand is not there.
01-11-15, 05:40 PM
#4
Actually by taller, I was meaning higher numerical ratio. Maybe I got the terminology backwards. If the ratio is 3.266:1 then here I mean going to something like 3.55:1 or 3.71:1. This would give snappier acceleration in exchange for a minor drop in fuel economy and a hit in top speed.
They do this in muscle cars and pickups all the time.
Just wondering if there's a gear set for this car. I believe the 2001-2003 cars are an open diff so it should be relatively simple for a shop. However not a lot of these cars were made so maybe the demand is not there.
They do this in muscle cars and pickups all the time.
Just wondering if there's a gear set for this car. I believe the 2001-2003 cars are an open diff so it should be relatively simple for a shop. However not a lot of these cars were made so maybe the demand is not there.
01-12-15, 11:44 AM
#5
Personally, I wouldn't touch it the rear gears.
The differences are so slight, you're probably talking a few nickels a month in gas savings. And swapping gears isn't like the old days, with all of the modern sensors communicating with the ECUs. It might require some sort of reflash to have an accurate speedometer.
Also, engineers in this day and age are pretty good about lining up their transmission with the gear ratio in order to the right blend of fuel economy and performance. A mismatched gear and transmission could actually give you both worse fuel economy and acceleration.
I could understand going with a numerically higher gear ratio for pure performance (and less fuel economy) but even then, the ratios are so close, I would be surprised if it even gave you a tenth of a second in the 1/4 mile.
It's not like the old days where you could drop in 4.10 gears into a Mustang in an afternoon and it's a night and day difference.
The differences are so slight, you're probably talking a few nickels a month in gas savings. And swapping gears isn't like the old days, with all of the modern sensors communicating with the ECUs. It might require some sort of reflash to have an accurate speedometer.
Also, engineers in this day and age are pretty good about lining up their transmission with the gear ratio in order to the right blend of fuel economy and performance. A mismatched gear and transmission could actually give you both worse fuel economy and acceleration.
I could understand going with a numerically higher gear ratio for pure performance (and less fuel economy) but even then, the ratios are so close, I would be surprised if it even gave you a tenth of a second in the 1/4 mile.
It's not like the old days where you could drop in 4.10 gears into a Mustang in an afternoon and it's a night and day difference.
02-01-15, 10:52 AM
#6
Lexus Test Driver
If I am faced with replacing both the transmission and the differential in my 5-speed A650E 2002 LS430, is there any benefit to using a later model A761E 6-speed transmission and/or differential? Is it even possible to install an A761E transmission in a 2002 LS430? It would be nice for my rpm's on the highway to be a little lower, other than that I am happy with the car.
Second, are ALL of the A650E transmissions the same? I've found a couple brand new ones for about $1,000 but they don't have the same part numbers.
Second, are ALL of the A650E transmissions the same? I've found a couple brand new ones for about $1,000 but they don't have the same part numbers.
02-01-15, 12:25 PM
#7
Pole Position
If I am faced with replacing both the transmission and the differential in my 5-speed A650E 2002 LS430, is there any benefit to using a later model A761E 6-speed transmission and/or differential? Is it even possible to install an A761E transmission in a 2002 LS430? It would be nice for my rpm's on the highway to be a little lower, other than that I am happy with the car.
Second, are ALL of the A650E transmissions the same? I've found a couple brand new ones for about $1,000 but they don't have the same part numbers.
Second, are ALL of the A650E transmissions the same? I've found a couple brand new ones for about $1,000 but they don't have the same part numbers.
Trending Topics
02-01-15, 12:44 PM
#8
The best bang for the buck and only easy option would be PPE headers and exhaust work. About 25 HP doing both. Intakes are not shown on any dynos to give any real hp. The lack of being being able to tune is what hurts intake modifications. Another option I don't see anyone doing is having the intake manifold honed out. Extrude honing I believe it's called. I think that could translate into 5 - 10 HP.
Last edited by Lavrishevo; 02-01-15 at 12:51 PM.
02-01-15, 12:53 PM
#9
Lexus Test Driver
I was just curious if they were an even swap. Not interested in doing any modifications. A few hundred lower rpm's would be nice at 80mph, but no big deal. Just figured if I need to change out the parts I would like to know my options.
02-02-15, 09:35 AM
#10
Pole Position
The A760e (I think that's the code for the 6 speed) isn't something you can swap into a 2001-2003 car.
The floor pan in the 2001-2003 car is different, the exhaust is slightly different, and the wiring harness and ECUs are different between the 2001-2003s and 2004-2006s.
A GS460 rear end would on a 2001 LS430 would create a taller final gear than 2004-2006 LS430s have. However a 2001-2003 LS430 rear end on the 2004+ LS430s would make a stupidly tall top gear.
The floor pan in the 2001-2003 car is different, the exhaust is slightly different, and the wiring harness and ECUs are different between the 2001-2003s and 2004-2006s.
A GS460 rear end would on a 2001 LS430 would create a taller final gear than 2004-2006 LS430s have. However a 2001-2003 LS430 rear end on the 2004+ LS430s would make a stupidly tall top gear.
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