ReGearing a V8?

[duffdog]

3.73 on v8

 

[midwestbandit]

Love this thread. Anyone have new input since 2015? [emoji16]


- Joshua Metcalf

 

[Inv4drZm]

Love this thread. Anyone have new input since 2015? [emoji16]


- Joshua Metcalf

Not much has changed. There are some other newer threads on this topic.

4.88s for the 4 speeds on 35's.
4.56 for everybody else on 35's.
Don't know if its financially worth regearing for anything smaller than 35's, unless you really want to do front/rear lockers, then you could regear at the same time.
4.88s for anybody on 37's.
5.29s for trailered rock-crawlers.

V6 vs V8, the V8 gives you a little more wiggle room.

 

[midwestbandit]

Not much has changed. There are some other newer threads on this topic.



4.88s for the 4 speeds on 35's.

4.56 for everybody else on 35's.

Don't know if its financially worth regearing for anything smaller than 35's, unless you really want to do front/rear lockers, then you could regear at the same time.

4.88s for anybody on 37's.

5.29s for trailered rock-crawlers.



V6 vs V8, the V8 gives you a little more wiggle room.

Yeah, I’ve got the V8, and have a LSD I’m about to put in the rear in the next week or two and was thinking about regearing while I’m at it, but I’m just running 33’s right now but would like to jump to 35’s in the future. I’ll probably just wait and regear when I get through this set of tires. Could be a couple years. Thanks!



- Joshua Metcalf

 

[Hwy88-Taco]

Updates to your tire size/gear ratio combos?

Did y’all die of the VID or you gonna give us the 2yr update on your tire size match to your gear opinions?:bump2:

For the last 18 months I’ve been running my BFG 35s on the stock 3:72 and HATING every mile towed while climbing 1,500’-8,000’ in the Sierras. Did some hwy 20 a while back and it reminded me that my money tree was ripe for the harvest. So I’m ready to throw $4K at gears.

As well as gears I did some homework :keyboard: on how money trees grow and decided to add a locker in the front. Now before y’all start flaming about how bad of an idea it is to lock a clamshell, just shove an aftermarket carrier in your diff-hole. :drum:That’s right, the aftermarket big brands all make a much tighter tolerance carrier than Toyota did. So while I could go cheap and just put a big brand carrier ONLY, but where’s the fun in that? So yeah, I’m gonna lock the front and hope to never use it for anything other than pulling jeeps out of the snow.

I called Nitro gears (aka Just Differentials) up in Wenatchee but they told me they’re on back order for the next month. Just gives me more time to get your feedback. Yes I know about ECGS, I spoke with both companies and they’re pretty close on $ as well as time.

Now give me some updates on the tires you ran for the last two years and on what gears? You tow too? Do you even climb brah! Sierras or Rockies or maybe the Grape Vine?

 

[Hwy88-Taco]

A750F-i gear ratio

After my last trip up 88 I figured out what I want out of my next gear set. Check out this chart to help make your decision. What I determined was that V gear aka 5th is 29% lower than 4th. That gear has been useless to me for anything other than long downhill grades since the dawn of my 35s. In 4th I’m pulling 2K at 70mph. So with my public education math skills, I decided to go roughly 30% deeper to get 5th gear back. 31% to be exact. :nerd:

3.727 x 1.29 (29%) = 4.80783. So 4.88 it is then. On the other end of the spectrum, the rest of the gears will now be 31% lower as well.

 

[aemravan]

Did y’all die of the VID or you gonna give us the 2yr update on your tire size match to your gear opinions?:bump2:

For the last 18 months I’ve been running my BFG 35s on the stock 3:72 and HATING every mile towed while climbing 1,500’-8,000’ in the Sierras. Did some hwy 20 a while back and it reminded me that my money tree was ripe for the harvest. So I’m ready to throw $4K at gears.

As well as gears I did some homework :keyboard: on how money trees grow and decided to add a locker in the front. Now before y’all start flaming about how bad of an idea it is to lock a clamshell, just shove an aftermarket carrier in your diff-hole. :drum:That’s right, the aftermarket big brands all make a much tighter tolerance carrier than Toyota did. So while I could go cheap and just put a big brand carrier ONLY, but where’s the fun in that? So yeah, I’m gonna lock the front and hope to never use it for anything other than pulling jeeps out of the snow.

I called Nitro gears (aka Just Differentials) up in Wenatchee but they told me they’re on back order for the next month. Just gives me more time to get your feedback. Yes I know about ECGS, I spoke with both companies and they’re pretty close on $ as well as time.

Now give me some updates on the tires you ran for the last two years and on what gears? You tow too? Do you even climb brah! Sierras or Rockies or maybe the Grape Vine?

I had ECGS built my 3rd member and clamshell when I decided to re-gear.

I am on 35's with A LOT of added weight. Steel bumpers, full drawer system, roofrack with hardshell RTT that stays on, winch, added armor, etc etc. I went with 4.56 gears because initially running 35's stock with the V8 really didn't seem to phase the rig at all. Plenty of torque to get around. My thought behind the 4.56 gears was that I'll get a bit closer to stock ratio while also retaining some beef in the ring/pinion since it's a well known fact that the higher to go, the smaller/less beefy the gear set gets.

With that said, after running this setup for the past year, I can say with confidence that I probably should have gone with 4.88 gears. Your math is pretty sound and I second the choice.

4.56's do OK, and I don't have it kicking down on my drives, but I also haven't done much mountain driving.. Offroad they do ok in 4lo with lockers, but yea, if I had to do it again I would definitely go 4.88.

Also, locker upfront.. yea.. I'm running ARB front and rear with RCV axles in the front. I can tell you first hand that yes, a locker is nice to have... but these front ends are tiny... I exploded the intermediate shaft and housing while fully locked, granted I had built up some wheel speed and then jammed my front passenger tire up against a giant boulder that made it come to an abrupt stop.. but nonetheless... you have to be careful with these tiny diff's we're running, especially if you have any weight to the rig like I do.


I'm really curious to see how these front ends hold up with all these guys running the RCLT kits with 37-40in tires

 

[LaZorChicKen]

I only re-geared my front and rear to 4.88. ECGS did my front and a local shop did my rear, i removed and installed myself. tried to rebuild myself too but its kinda technical, gotta get the right torque on the bearings and the preload. I couldn't quite dial it in myself, shop said i was real close though. Upgrade to a solid spacer while you're re gearing as well The difference compared to stock is incredible. I get the same gas mileage with 35s as i did with stock diff and tires. Huge upgrade for wheelin too, runner almost idles up the trail. lol

 

[Inv4drZm]

4.88s with 37s work great with my vvti V8. Can drive 80-85 on the interstate and keep up with traffic between Denver and Fort Collins. Also headers and dual x pipe exhaust.

MPG is calculated to be 13 or 14 from Kansas to Colorado, uphill. Back I didn't calculate but its usually 1 or 2 higher driving downhill.

When I had 35s with the 4.88s for a short time, it felt almost fast.