4.88’s and 32’s - honest opinions from a shitposter

I figured I’d share my thoughts on 4.88 gears in my 2017 TRD Off Road Automatic, running on LT275/70/17 tires, after 6 months living with the gears. I didn’t want to share any thoughts right away as I wanted the “gears honeymoon” to wear off completely, and have a chance for buyer’s regret to set in.

FYI: My truck has steel sliders, steel stub bumper and winch, steel rear bumper, and a fibreglass canopy with roof racks. I am running E-rated BFG Ko2 in 275/70/17 (just over 32”). My engine in not tuned, but has the latest OEM calibration for the ECU. You can check out what I’ve got bolted to the truck in this thread:

https://www.tacomaworld.com/threads/i-think-i’m-done-gonna-just-enjoy-it-now.736235/

Firstly, why did I regear my truck? Mostly on a whim, quite honestly. I had a bit of a financial windfall, and one day the lack of ‘ooomph’, off the line, with my added weight and heavy tires, started to pick at my brain. TW was, at the time, all about regearing and tuning, so when I got home one day I said “fuggit” and scheduled an appointment for Nitro 4.88s to get chucked in my diff housings. I figured “what do I have to lose?…….TW said it’s all unicorns and rainbows”.

So, after six months with these gears, here is my best attempt to be honest with myself, and TW, about the results. YMMV…..this is an opinion piece. My install was done by a reputable, specialized differential shop, that only does diffs, and they did an excellent job.

The Great:

Beast Mode! - the truck is a total beast in 4Lo. It has so much more low speed control and the engine doesn’t seem to be labouring on steep stuff, at all. The truck used to feel languid and struggling on steep off-road ascents, but now it charges up stuff like a champ. No complaints!

Controlled Reversing - Reverse gear is so much better with the gears. Toyota puts ridiculously tall reverse gears in these trucks in both the AT and the MT. I did not think I would notice any benefit of a regear in reverse, in fact it never even crossed my mind, but backing up is much better with the gears. You have a lot more time to react before you back into that fire hydrant!

The Good:

Stop and go traffic - My truck now crawls forward on level ground when you take your foot off the brakes in ‘D’, like it did on stock tires with stock weight. With my heavier tires and extra weight, the truck required throttle to get rolling on the factory gears, which was kinda weird compared to normal automatic transmission behaviour. It is now back to normal, which is nice. You can crawl along in bumper-to-bumper traffic, like before.

Linear shifting - My truck was never one that had the reported ‘gear hunting’, however, it did shift to a taller gear, sooner than I would like, due to Toyota’s fuel-conscious programming. Although the ECU still shifts up through the gears at lower than desirable RPMs (re-gearing doesn’t change the torque equations……you just end up in a higher gear sooner), all in all I feel the transmission shifting is way more linear and predictable on its way up. I feel this is because it essentially adds one more gear in the pattern as it steps its way up to cruising speed. All the times I previously would be cruising in 5th, I am now cruising in 6th, and the times I’d be cruising in 4th, I’m now in 5th, etc. That one extra gear step, as you accelerate your way up to cruising speed, makes the tranny logic seem more linear, like a modern 10 speed auto. In general, I didn’t have many complaints before, but now I honestly never think about the gear choice the auto is making, as the truck accelerates just fine.

Get up and go! - the off-the-line torque is way, way better. The truck has lots of ‘oomph’, and then some! (see “not so great” section for further comment on this)

No change in efficiency - My fuel efficiency did not get worse (thankfully), but, unfortunately, it didn’t get better either. It stayed pretty much exactly the same. I was hoping for an improvement, but didn’t see any at all.

6th is a thing! - if you were worried that you never got the break-in your sixth gear, because you were never in it, you are now in it all the time with 4.88s. The RPMs are reasonable too at highway speeds. Nothing crazy.

The not so great:

Whine! - the gears whine on deceleration. They are not crazy loud, but not silent like my factory gears either. The whine is comparable to a friend of mines stock 2nd Gen Taco Sport, so is not outside of what Toyota puts out there from factory. At the same time, any pride I had about my silent OEM 3G diff, compared to my buddy’s whining 2G diff, is gone. The sound of the whining diff is easily ignored, but it still cheapens the truck in some way. The installer did an exacting job, but before I got the work done, he assured me that all Nitro Gears whine, and anyone saying they don’t is either deaf, or justifying their purchase. He warned me that it was an inevitability before I ordered the gears. Needless to say, I got the whine. It’s not unbearable, and really only happens when letting off the throttle at speed, but is noticeable. It likely comparable to what unlucky people with the OEM Toyota whine complain about.

Slightly over-geared - The torque off the line is great, but is also less refined in its way. 4.88 is definitely over-geared on 275/70/17, in my opinion. This is not a statement about top-end cruising RPMs in 6th, but a statement of 1st gear being too low for what would be optimal refined shifting. Not a lot too low, but enough that anyone with an appreciation of how the truck drove stock, would notice it. The gear ratio is just that bit too aggressive to drive like a modern, refined vehicle should. 4.88s on 32’s is a little clunky off the line. It blasts through 1st gear much faster than would be “normal”. 4.56 would probably be perfect, but isn’t an option for the TRD OR 8.75” diff. I plan on going 33’s someday, so I will live with it being a bit stupid in the meantime. I will say, the Nitro Gear propaganda videos that basically say “4.88s are fine on a stock truck with stock tire size and no weight” are the statements of a madman. There is no friggin’ way I would drive a stock taco, on stock 30” P-rated tires, with 4.88s and be happy about it, unless I was exclusively rock-crawling my stock truck. Take my advice and don’t drink the Nitro Gear koolaid on this idea. Only regear if you got a heavy pig with beefy tires!

Harsh downshifts cold - when the transmission is cold, the downshift into 1st can be harsh. I never experienced this with the stock gears, but the shift down at a stop sign on 4.88s and 32’s is more aggressive than you would want when the tranny is cold. Once it warms up, it behaves itself, but the first couple downshifts on a cold morning can be harsh.

Dont get your hopes up! - Regearing does not change the factory transmission programming. The truck will still shift up through the gears to get you to a spot where you are cruising at 1100 RPM with no torque, like before. All those times you were in 4th at 1100RPM with no torque, you are now in 5th at 1100RPM with no torque. Those times when you were in 5th, you are now in 6th, and so on. Do not expect regearing to change your ECU programming. The ECU still wants to run the truck at low RPMs to save fuel, and will just do that in a higher gear selection than previous. If low RPM cruising is your only complaint, get a tune and skip the gears.

The bad:

No going back!! (but who would want to?) - The only thing I can think of is that the change is mostly a permanent one. The truck is now committed (or doomed) to running larger tires. Any fantasy I might have of returning my truck to stock format to sell it, or save fuel, would require an expensive regearing back to something lower than 4.88s, in my opinion. As I said before, 4.88s on dealer tires, with no added weight, would make the truck a jackass vehicle to drive around in. No thanks.

Final thoughts:

It is more positive than negative, and I don’t regret the change. It makes the truck a tiny bit more more clunky, noisy, and less refined, but the benefits outweigh those negatives. I am hopeful when I step up to 33’s some day, my few complaints will be lessened. Also, I am deeply glad I did not go with 5.29s. 5.29’s on 32’s would only be acceptable off road, in my opinion.

I hope this helps someone out there. Have a great Friday and weekend y’all.

 

I have 4.88 nitro gears installed by nitro gears and can hear the gears change more than stock, but don't hear any whine on my manual transmission.

 

Great write up.

We can try to get 4.56 from the Hilux, it is offered direct from Toyota.

 

Thanks. I did look into availability of the z Hilux 4.56 for the 8.75”‘diff. It seemed like an overseas import and a hassle. Knowing what I know now, I might have tried a little harder to track them down.

 

The grand irony, is that in the Nitro Gears own Tacoma regear vids on YouTube, you can hear the gears whining as the fella drives around, so even Nitro itself could not avoid the whine on their own truck. Count yourself lucky if you got a silent set (or get your ears checked ).

I hesitate to share this vid, as largely I think it’s 75% a sales pitch and 25% truth, but if you listen close, you can hear the gears whining. At 6:15 there’s is a good stretch where you can hear them whining. Again, it ain’t crazy loud, but is more present than on stock gears, at least in my case.

EDIT: looks like Nitro doesn’t allow the video to be linked (how dumb). Search YouTube for “nitro gears Tacoma” and look for the vid from Nitro.

https://m.youtube.com/watch?v=XxBWZGQIScI

 

These have been on my list for some time now. I really need to stop being lazy. Nitro gears is only 2 hours away.

 

Very nice well balanced write up, thanks & nice job.

 

It's completely ridiculous to make a small sound outweigh the results of stronger and more efficient gearing in a truck. Nitro Gears does great work and will even tell you that there might be a chance that you hear singing after a regear. My truck is 100% better after a regear with the weight I have.

 

interesting

 

I highly recommend getting the Overland Torque or Tailor Tunes after a regear as well.

 

I have 5.29s with 265/70r17s, tuned with that combo in mind while I do the supporting work to fit 35s.

If you let it idle in "D" on a flat surface it'll do a steady 4mph. It will idle up hill in reverse. 16mph highway/9-12mpg city.

It is so atrociously over geared that I've only used 4lo to allow my locker to engage.

How did I get here? I started with skinny 33s on stock suspension and stock gears. Got a great deal on the gears and install through a group buy. Wore out my 33s and needed new tires for a trip on short notice and could only find 265/70r17s in stock that would fit my setup and were meant to be a bandaid for just that trip until I could order another set more appropriate for my gearing as my new suspension was waiting to be installed. That was almost a year ago. I'm a stubborn man.

 

I think most of this should have been obvious beforehand. You changed your tire size by 3% and your gearing by 25%. If I were to change my gears I would try to do it to match my tire size.

On my 6mt: 33’s = 4.56, 35’s = 4.88, 37’s = 5.29. On the auto the available gear options clash with the stock 3.9 ratio. 34’s = 4.3, 35’s and 37’s = 4.56. But it’s geared rather high overall so going a bit steeper isn’t so bad.

 

I didn't see it jumping out at me, but are you on the stock leafs? I had a slight whine stock, but it quieted down significantly with an aftermarket pack. I really believe that our gear whine is what the TSB says, a harmonic in the rear end.

This is interesting. You are now at the same overall 1st gear ratio as the MT Tacos. Yeah, it is a bit short in truck style, but I'd still advocate 5.29s, even on a stock Taco as it just seems to be the right gearing? Of course, I am not denying your opinion or experience. I just have a different opinion.


Good stuff overall.

 

What rear bumper is that?

 

Enjoyed the write up, well done. Thanks

 

I've got 4.56's (8" diff) running 33's and a Magnuson with @mZiggy software and life is good. I don't regret buying 4.56's and not getting the forum favorite ratios 4.88/5.29

 

It’s an RCI. Here is my write up about it. Love it still.

https://www.tacomaworld.com/threads...ar-bumper-no-cut-version-bravo-to-rci.585102/

 

Do you have the non-OR 8” diff or did you buy the Hilux gears? Yeah I think 4.56 would be perfect.

 

I’m pretty sure I stated a few times I’m overall happy with the change in gearing. I’m just warning people that expect gear whine. Some will get lucky and have no whine, but most won’t, I’m guessing. You should expect it.

 

That’s gotta be wild torque levels on 265/70’s and 5.29s. You could probably pull the Eiffel Tower off it’s foundation.