Need some gear ratio input from LS Swap guys. (1 Viewer)

[Anthony Miller]

Here's my setup:

1984 FJ60
Vortec 4.8L 4L60E OD
stock 3.70 gears
33x10.50 BFG KM2's

I'm in the middle of the LS swap on my FJ60 and I've been thinking about gear ratios. After some calculating, I think 3.70's might be too tall for hwy driving. I'm figuring around 1800 rpm at 70 mph. I found some FJ62 diffs at a reasonable price and I think those would get me up around 2100 rpm at 70 mph.

My question is for the guys that have LS Swapped FJ60's with 33" tires. What gears are you running and are you happy with your setup?

I should note that this will be a daily driver with light wheeling.

 

[FJ60Cam]

I had 4.11s/33s/4L60e and thought it was perfect.

I’ve since gone to 35s and can feel a noticeable loss of power off the line. It also downshifts too often at highway speeds though that is probably because the computer is still programmed for 33s.

I say go for the 4.11s.

 

[Anthony Miller]

Thanks!

 

[bdyer12]

If you run tires smaller than 33s like me the 3:70 are great. I run 2100 at 70. I have 265/70/17s roughly 31.5

 

[NCFJ]

I am in the 4:11 crowd if running 33s. This drops you about in the middle of the ratios used in the GM 1500 HD and the 2500.

 

[pandasfj]

4:11 , 285/75/16 , 5.3l, I think works just fine, I don't plan on ever going over 33's.

 

[MANUCHAO]

I'm running 4.10 with 35".
At 70mph I'm at 2k rpm's...
PCM was also reprogrammed to run this set up...

 

[NCFJ]

I'm running 4.10 with 35".
At 70mph I'm at 2k rpm's...
PCM was also reprogrammed to run this set up...

This is important! When I have ECUs programmed, gear ratio and tire size are two very key pieces of information.