Just Put 4.88's in my 4Runner and.....

[Applejack]

So, long story short. A month or so ago my transmission (automatic) crapped out in '99 4Runner limited. I decided that while my trusted mechanic had it, that he should also drop in some 4.88's. My 4Runner has gained some extra heft since new and I thought that upgrading from its factory 4.30 ratio may be more kind to my new transmission.
Well I finally got it back today and even though I only got a chance to drive it across town, I am quite disappointed and underwhelmed by the "upgrade". How underwhelmed am I? Well, so underwhelmed that I don't notice any difference. None! Is anyone else surprised? Surely it has to have have more pep than stock, right?

 

[bkg]

have you validated you actually have the 4.88's? /cynic
what type of change were you expecting?

 

[nater]

It's a 10 percent change. It's not going to be dramatic in my experience, but you should verify.

 

[ExploringNH]

I went from 4.10 to 4.88 on my 02 4Runner with 33's (285/75/16) and it was an absolutely noticeable change. 4.30 to 4.88 is a smaller jump but I would still expect it to be noticeable.

 

[Applejack]

have you validated you actually have the 4.88's? /cynic
what type of change were you expecting?

Well nothing other than the receipt for the gears and installation labor. I suppose they could have accidentally put a different ratio set in. I was expecting it to at least get out of its own way. It honestly was so anemic in the low end that driving my daughters forester felt exciting. And I unfortunately have to say it as lackluster to drive now as ever. I should mention some specs like, I have not really oversized, but heavy 265/75/16 Cooper ST MAXX's, sliders, arb bumper , winch, and budbilt skids. Extra lbs. I wanted more snappiness off the line and more low end grunt for trails.

 

[brianjwilson]

It's a very small change. I do think you'll notice a difference as time passes, but depending on your stock tire size you're probably just barely back to stock performance. Not counting the heavier tires, increased rolling mass and resistance, weight of bumpers etc. I always try to gear so the net result is a bit lower than stock to help make up some of the losses.
The smallest jumps I've made were 4.10 to 4.88, and 3.73 to 4.56. The biggest was 3.73 to 4.88. I could hardly tell initially in town (except the one with a manual 6 speed trans). But as I put more miles on I felt more improvement on all. Holding gears longer on hills, better off the line when heavy, etc.

I will say that an automatic trans eats enough power to mask some of the gain. Especially if it is a weak shifting trans and a weaker torque converter. Hell I've watched some disappointing videos of supercharged tacomas with the stock automatic trans. Each shift under WOT takes a full second or better.

 

[Applejack]

It's a very small change. I do think you'll notice a difference as time passes, but depending on your stock tire size you're probably just barely back to stock performance. Not counting the heavier tires, increased rolling mass and resistance, weight of bumpers etc. I always try to gear so the net result is a bit lower than stock to help make up some of the losses.
The smallest jumps I've made were 4.10 to 4.88, and 3.73 to 4.56. The biggest was 3.73 to 4.88. I could hardly tell initially in town (except the one with a manual 6 speed trans). But as I put more miles on I felt more improvement on all. Holding gears longer on hills, better off the line when heavy, etc.

I will say that an automatic trans eats enough power to mask some of the gain. Especially if it is a weak shifting trans and a weaker torque converter. Hell I've watched some disappointing videos of supercharged tacomas with the stock automatic trans. Each shift under WOT takes a full second or better.

I'm hoping to find that it was worth dropping nearly $900 at some point. I will do some more driving with it tomorrow to do a more in depth assessment. What kind of burns me up about this whole deal is, for the past 6 months I had been kicking around the idea of either supercharging or regearing. I leaned away from supercharging because of having to upgrade the transmission valve body and fuel system upgrades, pushing the cost up to nearly $3k if I got a used s/c. As of today I paid $4k for tranny and gears, and none of it made it more enjoyable to drive. Yeah... I'm whining. I will stop now

 

[tonkaman]

The real test will be if your gas mileage increases. Maybe that bump will make it a bit more fun to drive

 

[2025 deleted member]

Do you know what your tach reading was at 65mph before? That's the easiest way to tell. I re-geared a truck from 3.73 to 4.10 and the difference was slight.

 

[brianjwilson]

I'm hoping to find that it was worth dropping nearly $900 at some point. I will do some more driving with it tomorrow to do a more in depth assessment. What kind of burns me up about this whole deal is, for the past 6 months I had been kicking around the idea of either supercharging or regearing. I leaned away from supercharging because of having to upgrade the transmission valve body and fuel system upgrades, pushing the cost up to nearly $3k if I got a used s/c. As of today I paid $4k for tranny and gears, and none of it made it more enjoyable to drive. Yeah... I'm whining. I will stop now

Adding a supercharger to a rig that is under geared is only going to make the transmission problem worse as you said. I think you did the right thing. Your drivetrain will appreciate it anyway. I would have gone lower personally but give it time. After running some familiar mountain passes or trails etc you might realize that it did more for you than you thought. At least that's how it usually works for me.

I'm still planning for my next truck, trying to figure out how to pay for a re-gear, supercharger and valve body upgrades on top of the rest of the stuff! Blows me away that I'll have to pull a valve body on a brand new Tacoma, send it off for rebuild and reinstall to make it shift right. My ford trucks just got a quick custom tune for the transmissions and it made a huge difference.

 

[Paddy]

Auto trans will mask a lot as its doing the feel for you. Also, new gears and new tranny will need to wear in, and new tranny might be set a little different too. It's a good thing to get gears, but it's expensive. On the up side, you should be able to sell the 4.30's for a decent coin to recoup some cost.

 

[CYi5]

We've got nearly identical setups at this point, but I did the switch from 4.30 to 4.88 a long time ago. I mainly did this while running 285/75, but since dropped down to 265/75 for better towing my teardrop (<1,000 lbs). It's still a dog regardless. I had 68 lb. treadwright wardens on for about two weeks, but the 4.88s and auto combo just couldn't keep them turning on slight inclines without downshifting. I recommend my friends to do 5.29's when their time comes, that way they could always go 35's if the need was felt.

 

[MaverickTRD]

I have a taco on 35s with 4.88 and a 4runner on 32s with the factory 4.30...while anecdotal I can most definitely tell a difference between the two. They drive very similar as they are, but i once put the 35s on my 4runner for giggle and it was a turd. More so than factory.

Personally though, I don't think that 4.30s are "undergeared" for the 3rd gen runners or 1st gen taco (not an available option on a taco factory) with the 3.4 and a tire that is 33 or shorter. I would definitely go up to a 4.88 with 35s though and on 33s it wouldnt hurt to gain some of that mechanical advantage i just dont view it as a requirement. and I agree that a supercharger would be a much more worthwhile purchase. I'm sitting over 2k rpm on the highway with my 4runner at times over 2500. I could add all the gear in the world and all it would do is decrease my highway mileage without gaining much pep whereas the s/c would give it the low end torque and power up top to help it perform how it should.

I wouldn't go higher than 4.88 in these trucks...the larger gear, the weaker it is...and 5.29s seem to experience a lot more breakage issues. heck with 4.88 and 35s on the taco I'm at 2400ish rpm at 70mph I wouldn't want to cruise at 3k on my daily commute

 

[PirateMcGee]

Well nothing other than the receipt for the gears and installation labor. I suppose they could have accidentally put a different ratio set in. I was expecting it to at least get out of its own way. It honestly was so anemic in the low end that driving my daughters forester felt exciting. And I unfortunately have to say it as lackluster to drive now as ever. I should mention some specs like, I have not really oversized, but heavy 265/75/16 Cooper ST MAXX's, sliders, arb bumper , winch, and budbilt skids. Extra lbs. I wanted more snappiness off the line and more low end grunt for trails.

If your tires are E rated I would switch to normal truck tires. Rotating mass kills performance coupled with a winch, arb, etc etc and you have the recipe for a dog. Maybe consider a front receiver and putting your winch on a cradle. Lightweight is the way to go IMHO.

 

[MaverickTRD]

Its simple imo. Without more power these things will always be dogs. Bone stock or armored to the teeth...but at least they seem to keep going and going and going.
a little less speed allows you to take in more scenery and 4lo should provide all the grunt you need on a trail