FJ80 vs FZJ80 stock gear ratio + crawl speed (1 Viewer)

[ozarkmud]

From what I understand, the FZJ80s have 4.10 gearing in the differentials. Do FJ80s have the same? I can't quite tell.

With that, is the 4Low crawl behavior different between the FJ80 and FZJ80? One of the biggest disappointments of the FZJ80 for me is the crawl speed in 4Low. It's not even close to a Pickup or 4Runner. Part of that is auto vs manual, but I also think the ratio is much higher. I like having a low ratio for going down hills.

 

[nukegoat]

Same, and super low crawl ratios are lame anyway

 

[-Spike-]

Same diff ratios. I'm not sure about Fj80's, but early FZ's have a lower first gear than '95+, so there is a difference in first gear crawl ratios. And low ratios rock. Not sure what defines 'super low', but with an auto trans there is probably a point of diminished return. Personally, I'm pretty happy with 20% lower than stock drivetrain ratio running 37" tires- which makes it pretty close to a stock final ratio including the rubber.

 

[ozarkmud]

I'm wondering if a reduced transfer case ratio would work, or if a manual swap is necessary. I've been in a couple of situations where touching the brakes would lock things up, but descending in 4 low was nicely controlled.

It sounds like there's 20% and 25% reduction kits available.

There's also imported diesels with manuals. How is the engine braking on those, without a throttle to control?

 

[Dusten]

From what I understand, the FZJ80s have 4.10 gearing in the differentials. Do FJ80s have the same? I can't quite tell.

With that, is the 4Low crawl behavior different between the FJ80 and FZJ80? One of the biggest disappointments of the FZJ80 for me is the crawl speed in 4Low. It's not even close to a Pickup or 4Runner. Part of that is auto vs manual, but I also think the ratio is much higher. I like having a low ratio for going down hills.

The w56 has a 3.94:1 first gear ratio
The a340 has a 2.80:1 first gear ratio
The rf1a has a 2.28: low range
Most manuals came with 4.10s
Most autos came with 4.30s


With 4.10s that's a 37:1 crawl ratio
With 4.30s that's a 27.45:1 ratio


The a442f has 2.95:1 first gear
The a343f has a 2.804:1 first gear
4.11 axles
Hf2a/v has a 2.49:1 low range

The a442 has a 31:1 crawl ratio
The a343f has a 28.7:1 crawl ratio

They really aren't that different

 

[Dusten]

Same diff ratios. I'm not sure about Fj80's, but early FZ's have a lower first gear than '95+, so there is a difference in first gear crawl ratios. And low ratios rock. Not sure what defines 'super low', but with an auto trans there is probably a point of diminished return. Personally, I'm pretty happy with 20% lower than stock drivetrain ratio running 37" tires- which makes it pretty close to a stock final ratio including the rubber.

The 95+ has a taller first gear.

 

[jonheld]

From what I understand, the FZJ80s have 4.10 gearing in the differentials. Do FJ80s have the same? I can't quite tell.

With that, is the 4Low crawl behavior different between the FJ80 and FZJ80? One of the biggest disappointments of the FZJ80 for me is the crawl speed in 4Low. It's not even close to a Pickup or 4Runner. Part of that is auto vs manual, but I also think the ratio is much higher. I like having a low ratio for going down hills.

There are many threads regarding transfer case gearing.
Yes, FZJ and FJ80s have the same axle ratios and same transfer case gearing.
To add to what @Dusten mentioned, the A440F in the 91/92 has a 2.950 first gear.

On a personal note, I am extremely happy with the combination of 4.88 in the diffs and 3.1 low range transfer case gears.

 

[ozarkmud]

Thank you for the info!

I'm a little surprised at the difference between manual first gears and automatic first gears: Transmission Ratio Information - Marks 4WD - https://www.marks4wd.com/transmission-ratio-information

The manual first gears are considerably lower. Even the FJ60's H42 seems like it would work decently well.

 

[Dusten]

Thank you for the info!

I'm a little surprised at the difference between manual first gears and automatic first gears: Transmission Ratio Information - Marks 4WD - https://www.marks4wd.com/transmission-ratio-information

The manual first gears are considerably lower. Even the FJ60's H42 seems like it would work decently well.

A manual first gear needs to be, because you don't have torque multiplication from the converter.