Gearing question for 89 4runner 5spd 3.4 swap
07-22-2014, 03:44 PM
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Gearing question for 89 4runner 5spd 3.4 swap
hi there i have a gearing question. currently i have an 89 4runner with the 3.4 swap. It is a 5speed and has stock 4.10 gears.
I am running 32x11.5s but will eventually be going for 33x12.5 and no larger ever.
So with the swap i have is 4.88 my best bet?
i recently went on a hwy drive and going 100km/h(60mph) in 5th i was sitting just over 3000rpm. going about 120 i was at just over 3500rpm.
To me that is to high for the rpm to be and it seemed to suck an entire tank of fuel in less than 300km.
So i was thinking i have a gearing problem, i want to maintain my power but drop the rpm for when i am cruising on the hwy. So again is 4.88 gears the best route for me to go with my setup?
thanks for the help!
oh and has anyone used the gears from trail gear? trail creeper i believe?
I am running 32x11.5s but will eventually be going for 33x12.5 and no larger ever.
So with the swap i have is 4.88 my best bet?
i recently went on a hwy drive and going 100km/h(60mph) in 5th i was sitting just over 3000rpm. going about 120 i was at just over 3500rpm.
To me that is to high for the rpm to be and it seemed to suck an entire tank of fuel in less than 300km.
So i was thinking i have a gearing problem, i want to maintain my power but drop the rpm for when i am cruising on the hwy. So again is 4.88 gears the best route for me to go with my setup?
thanks for the help!
oh and has anyone used the gears from trail gear? trail creeper i believe?
07-22-2014, 06:38 PM
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You need to get a GPS and find out how fast you're really going, and preferably do it before you get a ticket. With 4.10 gears and 32 inch tires, the math says you're doing a little over 80 mph at 3000 rpm in 5th gear.
With the 3.4, I don't think I'd change the gears. It obviously has plenty of power to haul butt in its current configuration. I think your main issue is a speedometer calibration problem.
With the 3.4, I don't think I'd change the gears. It obviously has plenty of power to haul butt in its current configuration. I think your main issue is a speedometer calibration problem.
Last edited by RJR; 07-22-2014 at 06:43 PM.
07-22-2014, 07:20 PM
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Then there's something else wrong with this picture. Here's the assumptions:
tire diameter = 32 inches
5th gear ratio = .851
rear end ratio = 4.10
From there it's straightforward math to calculate mph vs rpm, and 3000 rpm yields 81.8 mph.
One of those three numbers up there isn't right.
tire diameter = 32 inches
5th gear ratio = .851
rear end ratio = 4.10
From there it's straightforward math to calculate mph vs rpm, and 3000 rpm yields 81.8 mph.
One of those three numbers up there isn't right.
07-22-2014, 08:26 PM
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Nothing wrong with going over 3k rpm, If you have to lay into the throttle to hold speed then your under geared.
With what I have heard from other 3.4 owners 4.30 - 4.56 are fine for everything up to 34", 4.88 for 35" and up.
With what I have heard from other 3.4 owners 4.30 - 4.56 are fine for everything up to 34", 4.88 for 35" and up.
07-23-2014, 05:30 AM
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Then there's something else wrong with this picture. Here's the assumptions:
tire diameter = 32 inches
5th gear ratio = .851
rear end ratio = 4.10
From there it's straightforward math to calculate mph vs rpm, and 3000 rpm yields 81.8 mph.
One of those three numbers up there isn't right.
tire diameter = 32 inches
5th gear ratio = .851
rear end ratio = 4.10
From there it's straightforward math to calculate mph vs rpm, and 3000 rpm yields 81.8 mph.
One of those three numbers up there isn't right.
ok wow, this isnt good then because 3000rpm is 60mph.... thats quite the difference in numbers!!
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07-23-2014, 03:08 PM
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07-23-2014, 06:17 PM
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Since yotes86 (the OP) has an '89, I was assuming a G58 transmission, which has a 5th gear of .851. Either way, that would only change the calculated speed from 81 to about 83 mph. Doesn't explain the discrepancy in the numbers.
Yotes86, are you absolutely sure you have 4.10 gears? If they were 5.29's, that would come pretty close to explaining the difference.
Yotes86, are you absolutely sure you have 4.10 gears? If they were 5.29's, that would come pretty close to explaining the difference.
07-23-2014, 09:29 PM
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Since yotes86 (the OP) has an '89, I was assuming a G58 transmission, which has a 5th gear of .851. Either way, that would only change the calculated speed from 81 to about 83 mph. Doesn't explain the discrepancy in the numbers.
Yotes86, are you absolutely sure you have 4.10 gears? If they were 5.29's, that would come pretty close to explaining the difference.
Yotes86, are you absolutely sure you have 4.10 gears? If they were 5.29's, that would come pretty close to explaining the difference.
07-24-2014, 04:53 AM
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I have the exact same setup. 3.4 swapped (where a 3VZE was) with R150F and 4:10 rear with 32x11.5 BFG mud terrains. at 3000 rpm I am at 81mph. This is confirmed with the onboard tach, a OBDII gauge that is reading directly from ECU and GPS.
My guess is that either your tach reading is off (likely if the tach mod was not successful), your speedo is off (more unlikely), or you have non-original gearing. (Most likely)
My guess is that either your tach reading is off (likely if the tach mod was not successful), your speedo is off (more unlikely), or you have non-original gearing. (Most likely)
07-24-2014, 07:39 AM
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I have the exact same setup. 3.4 swapped (where a 3VZE was) with R150F and 4:10 rear with 32x11.5 BFG mud terrains. at 3000 rpm I am at 81mph. This is confirmed with the onboard tach, a OBDII gauge that is reading directly from ECU and GPS.
My guess is that either your tach reading is off (likely if the tach mod was not successful), your speedo is off (more unlikely), or you have non-original gearing. (Most likely)
My guess is that either your tach reading is off (likely if the tach mod was not successful), your speedo is off (more unlikely), or you have non-original gearing. (Most likely)
07-24-2014, 07:47 AM
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It's pretty easy to check the gear ratio. Assuming open differentials, jack up one rear wheel and rotate it 2 turns. Count drive shaft revolutions. If it's a bit over 4, you've got the 4.10. If it's a bit over 5, you have the 5.29.
For more accuracy, rotate the wheel 20 turns, count drive shaft revolutions, and divide by 10. This usually requires a helper to keep track of the separate counts unless you're really good at multitasking.
If the rear diff has a locker, the procedure is the same except you need to jack up both rear wheels and turn them 1 or 10 times, respectively.
For more accuracy, rotate the wheel 20 turns, count drive shaft revolutions, and divide by 10. This usually requires a helper to keep track of the separate counts unless you're really good at multitasking.
If the rear diff has a locker, the procedure is the same except you need to jack up both rear wheels and turn them 1 or 10 times, respectively.
07-29-2014, 09:02 PM
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It's pretty easy to check the gear ratio. Assuming open differentials, jack up one rear wheel and rotate it 2 turns. Count drive shaft revolutions. If it's a bit over 4, you've got the 4.10. If it's a bit over 5, you have the 5.29.
For more accuracy, rotate the wheel 20 turns, count drive shaft revolutions, and divide by 10. This usually requires a helper to keep track of the separate counts unless you're really good at multitasking.
If the rear diff has a locker, the procedure is the same except you need to jack up both rear wheels and turn them 1 or 10 times, respectively.
For more accuracy, rotate the wheel 20 turns, count drive shaft revolutions, and divide by 10. This usually requires a helper to keep track of the separate counts unless you're really good at multitasking.
If the rear diff has a locker, the procedure is the same except you need to jack up both rear wheels and turn them 1 or 10 times, respectively.
probably going to need to get some gears as i get ˟˟˟˟ gas mileage cant even go 300km to a tank like wtf
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