5.29's with High Range Under-drive T-case Gears (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Road Apple

SILVER Star
Joined
Nov 28, 2011
Threads
41
Messages
1,350
Location
Santa Cruz, CA
Ready to re-gear the diffs and t-case to crawl the Sierras on 37's. I'll be adding both under-drive and low range reduction t-case gears. My decision is between loading the diffs with 4.88's or 5.29's. I want to gear down as low as possible for the trail, but don’t want to be stuck in the slow lane getting there.

Putting aside the strength debate between 4.88's and 5.29's, I'd like to know how these gear combination worked out for you.

I've read multiple comments from people with 37's, both sets of t-case gears, and 4.88's saying they were happy on the highway driving 75+ mph with no problem, but wish they had lower gearing for crawling. I can't find anyone running the same setup with 5.29's.

Anyone with 37's, both sets of t-case gears, and 5.29's?

How is the truck in the highway? Is the gearing too low for the road? Is the minor difference in gearing between 4.88' and 5.29's even worth my over thinking?
 
Last edited:
5.29's and just crawler gears. Like above, 75 on the Speedo, but only doing 60 something per GPS.
I installed the crawler gears while doing my LS swap. The 4L60e has a lower first gear than the stock 80 trans. I'm happy w/ it, but wish I could get as low as my old Dual Ultimate set up I had in my mini truck and 2nd gen 4runner crawlers.
My final crawl ratio on the 80 is 50.5:1. My old minis it was 206.6:1
 
I'm running 37s and 5.29s with the 3.11 t-case gears.

Off-road - The low range is good, but not great. The truck is just too damn heavy. It could really use a 2x reduction.
Highway - Runs well, usually up around 3k rpms. I turn off the overdrive on big hills, but that's about it. I'm also running a really heavy tire and wheel combo, so YMMV.
 
5.29's and just crawler gears. Like above, 75 on the Speedo, but only doing 60 something per GPS.
I installed the crawler gears while doing my LS swap. The 4L60e has a lower first gear than the stock 80 trans. I'm happy w/ it, but wish I could get as low as my old Dual Ultimate set up I had in my mini truck and 2nd gen 4runner crawlers.
My final crawl ratio on the 80 is 50.5:1. My old minis it was 206.6:1
What RPM does that put you at? I always run around 80 on the interstate. I’ve been pondering 4.88s or 4.56 with the underdrive gear in the t-case.
 
5.29's and just crawler gears. Like above, 75 on the Speedo, but only doing 60 something per GPS.
I installed the crawler gears while doing my LS swap. The 4L60e has a lower first gear than the stock 80 trans. I'm happy w/ it, but wish I could get as low as my old Dual Ultimate set up I had in my mini truck and 2nd gen 4runner crawlers.
My final crawl ratio on the 80 is 50.5:1. My old minis it was 206.6:1
You old mini had a 4 banger and probably a manual trans. The 80 has a good torque converter that multiplies torque by 2. The big draw back with any auto is lack of transmission braking.
 
Ready to re-gear the diffs and t-case to crawl the Sierras on 37's. I'll be adding both under-drive and low range reduction t-case gears. My decision is between loading the diffs with 4.88's or 5.29's. I want to gear down as low as possible for the trail, but don’t want to be stuck in the slow lane getting there.

Putting aside the strength debate between 4.88's and 5.29's, I'd like to know how these gear combination worked out for you.

I've read multiple comments from people with 37's, both sets of t-case gears, and 4.88's saying they were happy on the highway driving 75+ mph with no problem, but wish they had lower gearing for crawling. I can't find anyone running the same setup with 5.29's.

Anyone with 37's, both sets of t-case gears, and 5.29's?

How is the truck in the highway? Is the gearing too low for the road? Is the minor difference in gearing between 4.88' and 5.29's even worth my over thinking?
The 10% under drive gears plus 5.29’s would be like having 5.82 r&p gears. You can find calculators on the internet to know what your rpms will be at any speed. The torque of the 1fz peaks at 3200.
 
Same as most others, 5.29s, 37s, 3.11 low range gears.

IMO 5.29s and 37s work just fine for highway speeds.

3.11 gears are a nice improvement over stock, but hardly adequate for crawling and leave much to be desired. I'm not sure the additional 10% reduction from the high range underdrive gears is worth the cost, but I haven't driven one to know the difference.

I don't know what Toyota was thinking in the 90s with the lame 2.488 transfer case gearing. At least the newer rigs are getting better options. A Rubicon is what, like 4.1? And the Bronco is 3.06 with a super lower crawler gear for manual transmissions of 6.588
 
What RPM does that put you at? I always run around 80 on the interstate. I’ve been pondering 4.88s or 4.56 with the underdrive gear in the t-case.
Man to be honest i don't really remember..... I sometimes fell it's a little over geared w/ 5.29's to be honest.
 
Same as most others, 5.29s, 37s, 3.11 low range gears.

IMO 5.29s and 37s work just fine for highway speeds.

3.11 gears are a nice improvement over stock, but hardly adequate for crawling and leave much to be desired. I'm not sure the additional 10% reduction from the high range underdrive gears is worth the cost, but I haven't driven one to know the difference.

I don't know what Toyota was thinking in the 90s with the lame 2.488 transfer case gearing. At least the newer rigs are getting better options. A Rubicon is what, like 4.1? And the Bronco is 3.06 with a super lower crawler gear for manual transmissions of 6.588
No one made a transfer case lower than the mid 2’s:1 that I know of until jeep put 4:1 in the their tin can. The revered NP205 was only 1.98:1 and the 203 about the same. Later on New process made a few cases that are in the mid 2’s just like the hf2a. I’m pretty sure that gear ratios are chosen by manufactures based on the intended use of the vehicle and demands of general public.
 
The 10% under drive gears plus 5.29’s would be like having 5.82 r&p gears. You can find calculators on the internet to know what your rpms will be at any speed. The torque of the 1fz peaks at 3200.
The calculator helped a lot. Thanks. These numbers are fine for getting to the trail.

9F9893EC-C637-4928-B63D-24BE0B9B8B0E.png
 
Last edited:
The calculator helped a lot. Thanks. These numbers are fine for getting tongue trail.

View attachment 2582573
We’re you able to input the actual OD ratio into that calculator? For instance, my dodge Cummins has an OD of .67. In think the A442f is something like .82 or .85. Not sure about the A443. This info is easy to obtain though.

2659rpm seems low for the Landcruiser with 5.82 gears because mine, with true 37’s and 4.88’s is 2500-2600 at 70 and my Speedo is dead on.

My guess is that the calculator input a generic number for the OD reduction calculation.
 
We’re you able to input the actual OD ratio into that calculator? For instance, my dodge Cummins has an OD of .67. In think the A442f is something like .82 or .85. Not sure about the A443. This info is easy to obtain though.

2659rpm seems low for the Landcruiser with 5.82 gears because mine, with true 37’s and 4.88’s is 2500-2600 at 70 and my Speedo is dead on.

My guess is that the calculator input a generic number for the OD reduction calculation.
I agree...the numbers aren’t accurate, but it gives a general idea. No, I haven’t found a calculator that has the A442F transmission in the drop down menu. Still hunting.
 
Last edited:
Mark’s has a better calculator than Spicer.

edit:
It has selections for tire dimensions, Toyota transmissions, diff ratio, and t-case high and low range (25% 3.11:1 reduction....1.1 for high range)

You input RPM’s and it gives speed in kph for each gear.


At 3200 RPM in overdrive your speed would be 67 MPH. In drive, 60 MPH.

Pretty slow for the highway.

976BA896-36F9-4C3C-90B2-63D4C177B4CC.png


94A68AC1-E492-44D4-B7E7-972766005F00.png
 
Last edited:
I don’t know what year your rig is but I did some math for an A442f. The calculators show 3900rpm for auto without OD and 3700rpm for “manual”. I used the 3900 and multiplied by .765 OD reduction of the tA442f and came up with 2983rpm at 70mph. Most 37’s fall short of 37” so you can figure 3,000rpm.

3k isn’t terrible but when you are at higher elevation and climbing a steeper grade 2nd gear is usually necessary to maintain any kind of speed. Being at 3k rpm in OD at 70mph will put you well up in the 4k’s of rpms to run 50 in second gear.

It costs a lot of money to be happy in all circumstances.
 
Thank you @baldilocks. Your numbers are solid and sobering. I initially loaded the Mark’s calculator for my ‘97 LX450 with .9 for high range with under-drive, but the correct number is 1.1. That made a significant difference in RPM vs MPH and match up much closer to you calculations.

The calculations shown in the above post have been edited.
5.29's with 10% under-drive
67 MPH @3200 rpm in overdrive
60 MPH @3200 rpm in drive

That’s just too slow for my lead foot. I’m going to stay with 4.88’s, 10% underdrive and 25% low range reduction.

edit: add

I’d like to be at 75 MPH at 3200 rpm.
This looks like the sweet spot.
4.88’s with 10% under-drive
74 MPH at 3200 rpm in overdrive
65 MPH at 3200 rpm in drive

Appreciate everyone’s input. Thank you MUD
 
Last edited:
Good decision I do think.... now, if I could gather the motivation to pull my case one more time to install the under drive gear set...
 
Last edited:
To share with you - My set up is 37's, 4.88's , 3.1:1 Low Range Gears HF2A and Under Drive Gears HF2A. With that said at 75-80 the tach is at and then over 3000. I'm not a fan of the higher RPM's on the interstate. My plan is to remove the under drive and put the stock final drive gear back it in. This gearing feels great when pulling grade in the mountains. I drove out-west to run the Rubicon last July and I appreciated in Colorado and in California but the flat states sucked, I didn't like running the higher RPMs for hours on end.. To keep things in perspective, elevation around here at most is 900' so I think I'll be happier running a bit lower RPMs.... your signature reads you're from Cali so you may never be bothered by it.
good luck
 
Last edited:
Why not go stock high range/3.1/5.29s? That should be slightly taller high range, and lower low range than the UD high/3.1/4.88s
Correct me if I’m wrong. From what I’ve read, the high range UD is added to the low range gearing when 4Lo is engaged. If so, then the UD high / 4.88 gearing is about the same as stock high range / 5.29’s.

The parts are already in hand. Almost a year ago, I bought 4.88’s, high range, and low range gears with the thought that 4.88’s would be slightly stronger than 5.29’s. Parts delays from Australia have delayed the build for over 7 months, so I’ve had too much time to think “What if.”

I want to gear down as low as possible for crawling. The recent Doubler/Black Box thread comments and desires to gear way down got me thinking 5.29’s might work out better than 4.88’s.



7FD65869-28E5-4D6B-AAEB-4483B0AF53E1.jpeg
 
Last edited:

Users who are viewing this thread

Back
Top Bottom