Gears -- 4.56 or 4.88?

[OGBeno]

This is a great thread. Thanks all for the enlightenment, as I am getting ready to do a gear upgrade soon.

One question: Does Toyota make 4.88 gears for our rigs? Dan...any comment?

Thanks.
-onur
Akron, OH

 

[cruiserdan]

There are 4.88 Toyota gearsets. They are not standard 80 series fare. I believe they are from some 7- series. The late 7-series uses a top pinion front like the 80 does. They could be mine trucks? I do not have part numbers and I have no way of easily finding out. If the price is similar to the stock 4.10 gears which is reasonable to assume, one ring and pinion set would be over 700 bucks.

 

[OGBeno]

If the price is similar to the stock 4.10 gears which is reasonable to assume, one ring and pinion set would be over 700 bucks.

Thanks Dan. I'll pass on those and go with a quality aftermarket...Summit Racing is ten minutes away!!


-onur
Akron, OH

 

[reffug]

Why do these guys with forced induction jump in these gearing threads with their opinions. BUGGER OFF!

Cause we can.

 

[Nay]

It is important to remember that the higher (numerical) you go the gears get weaker. It's a lot easier to break 5.29 gears than 4.10 gears. I still takes effort to do so but not quite as much. Ironicly we install weaker gears in order to work the vehicle harder....

The question remains as to whether the R&P becomes the weak point on 5.29. It would have to be weaker than stock birfs. And of course, if the lower gears help you maintain control and limit shock loading, then you are probably in better shape independent of the empircal data.

Nay

 

[nakman]

This is great stuff guys, I'm glad I revived this old thread it definitely got some nice new life to it, thanks! I'm convinced now that 4.88 is where I need to go if I expect to run 35's some day.. as it stands right now I get down to about 30-35mph approaching Eisenhower tunnel. and that's sad..

 

[willie]

I was having the same debate about a year ago when getting ready to regear. I chose 4.88's and I am VERY HAPPY with these. It's a big heavy rig and these give me half a run up a mountain grade (as long as I draft behind a greyhound). 4.56's would not be enough gear for mountain roads. And the truck cruses highway speeds without huffing. I too had a CJ7 with SB and TH400. And you're right it was way too low geared for highway running - not the case at all with the LC. Good luck - you'll like the 4.88's.

 

[spressomon]

Some are going the other way on that debate.

http://www.gearinstalls.com/410suck.htm

Great article! Thanks for posting!

 

[cc93cruiser]

I am getting 35's on my cruiser too, and after reading this post, I will too be regearing to 4:88's instead of the 4:56's............Thanks for all the input fellows....

 

[FirstToy]

Some are going the other way on that debate.

http://www.gearinstalls.com/410suck.htm

That is interesting. All things being equal (tooth depth, contact w/ring) doesn't the fact that the 5.71 spins faster, additionally b/c the teeth are spinning on a smaller diameter, the actual teeth are spinning even faster?

So maybe this contributes to wear and possible breakage?

I do agree that install is the crucial factor. Thinking ahead for this, 4.88 or 4.56 does not worry me. A good install does!

 

[ShottsUZJ100]

Is your truck done yet HONDO? I bet you'll like the 4.88's. I luv them in the LX. Rather than added power, the thing I like the BEST about having them is the added crawl ratio. Man, going down steep hills on the trail.....no brakes most of the time. How smoky is it in Flag from the Brigs Fire?

 

[alvarorb]

Is your truck done yet HONDO? I like the BEST about having them is the added crawl ratio. Man, going down steep hills on the trail.....no brakes most of the time.

John,

You must be going down grated Forest Service roads. I have 4.88s on La Cabra, and they will slow her down, but not to make her crawl.

Regards

Alvaro

 

[ShottsUZJ100]

John,

You must be going down grated Forest Service roads. I have 4.88s on La Cabra, and they will slow her down, but not to make her crawl.

Regards

Alvaro

It's "graded".

Compared to 35's and stock gearing.....the thing "crawls" with 4.88's.

 

[Letsgomoreplaces]

4.88

4.88 would be a great combo. It is not much lower than 4.56 and all of us seem to carry a bit more weight than stock and could benifit from a few more rpm

 

[CruisinFJ60]

Bump...

 

[Corbet]

4.88

 

[n00g7]

Every time I see one of these threads, I wonder why we don't have a 5.13 option. A tad deep for 35's, a tad tall for 37's... but perfectly matched to crawling gears w/ 37s, sounds perfect if swapping 315s for road and 37s for off road.

 

[Dragos80]

I am getting a set of 35''s soon, still running stock gears and of course rehearing came into play. I live in LA, pretty flat here, until you hit a nice long grade coming back home from the Valley for example. The Grapevine is a nasty long stretch of freeway where my stock geared 80 on 33", not loaded, struggles a bit at 6% for 6.5 miles.
A lot of people apparently are trashing the 4.56 setup.

I played with the gear calculator on tacomaworld using different gears and tire sizes. To me it looks as if the 35's are better suited with 4.56 since it brings it almost dead on to stock form. Stock form being a good compromise between power band, fuel economy, reliability/longevity, engine noise, etc.

Disclosure: All this is theory. YMMV in real life.

Running everything stock, at 65mph on 31" the RPM is at 2881 (this doesn't sound real, maybe because the calculator is set for a Tacoma gearing???)

Running 33's on stock gear 4.11 gets you lower RPM (2734), little less real on the road power and slightly higher real speeds compared to the speedo.

Running 35's on the calculator with stock gears gets you in a nice overdrive mode (2594) while on nice on a flat surface, a real pain I assume at elevation.

Looking at 4.56 gears on 35's the RPM is almost at stock figures.
I drove a diesel for way too long I guess and seeing just over 3000RPM at 65MPH makes me nervous, especially since the 1FZ is not a performance race engine, it actually behaves more like a diesel in terms of power band at low to mid RPMs.

I also plan on switching back and forth between 33's and 35's, with the larger tires for more off road trips and 33's for DD in the city.
As you probably guessed it, I am leaning toward the 4.56 setup. It looks to me if I am running 33's on 4.88 it would be overkill.

Also, I am considering a supercharger in the future, so the lack of a lower gear (4.88) might be mitigated by the increase in power.

I think @NLXTACY has a s/c and 35's, but not sure about the gears if they're stock or otherwise. @Qball was also bragging about his truck behaving really nice on 35's I think, but not sure if his engine is blown or stock. I have no idea about his gears either.

Am I heading in the right direction with my setup? 4.56 gears, interchanging tire sizes (33's and 35's), and a possible supercharger in the future?

Valley boys, you can chime in at anytime. BTW, I'll be in the neighborhood on Saturday, picking up the tires.

 

[n00g7]

I have no specific experience on the 80 with regearing yet, but I usually calculate what the stock equivalent would be and go up one further.

Reason: Weight. Gearing to stock ratio gives you the same advantage over the larger radius, but there's more mass to rotate. Plus, I've added many hundreds of pounds over stock with bumpers and winch too... not to mention when I get sliders and armor out the underside. And my 80 is packing more mass than my other rigs too since the bumpers, armor, etc. are all bigger and heavier.

With the 75+ speed limits (if I'm actually driving them), I don't notice much more downshifting with 35's than 33's... because it already happened on virtually every incline. Slower speeds through hill country, I had to burry the pedal with 33's, and of course still have to with 35's on stock gears. I personally wouldn't bother regearing to 4.56.

 

[chap79]

I played with the gear calculator for months before making my purchase. I ran 4:88 on my last FZJ80 with 35" tires and if I go back to that size on this one I would repeat the same. I drove my armored 80 over the grapevine in 35's with stock gears full with family and towing the motorcycle. I'm hated every minute of it. With 4:88's it was much more enjoyable. I could cruise at 75 all day with no problem on the freeway.

4:56's are probably fine for a truck without armor and not carrying a bunch of stuff for the trail. But once you load these beast down you'll be wanting a little more.