Was the gear swap worth it off and on the road? Or would you have stayed with the 4.30?
4.88 owners
- Thread starter bull
- Start date
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gear swap
As far as I am aware, Christo and I are the only ones have regeared our 100's. I would say that it was definately worth it and I only run 33's. It is my commuting vehicle and my tow-vehicle and I would say that mileage is mostly unchanged. Keep in mind that I also have heavy drawers, winch, arb bar, etc. If anyone is interested in regearing we can do this at our shop in Everett, WA. Or call Christo. Short of all the cruisers that I have had, I just don't see too many late model modified cruisers.
Carl
As far as I am aware, Christo and I are the only ones have regeared our 100's. I would say that it was definately worth it and I only run 33's. It is my commuting vehicle and my tow-vehicle and I would say that mileage is mostly unchanged. Keep in mind that I also have heavy drawers, winch, arb bar, etc. If anyone is interested in regearing we can do this at our shop in Everett, WA. Or call Christo. Short of all the cruisers that I have had, I just don't see too many late model modified cruisers.
Carl
sleeoffroad
Supporting Vendor
I always felt that 5.29's with the 325/65/18's that I run would have been better. However I don't mind running motors at higher rpm's. For most people the 4.88's would probably be ok.
- Thread starter
- #4
I'm interested in 4.88s I understand since I have the electric locker I will need to obtain a diff carrier case from a 93-97 rear diff w/ oe locker.
That being said while I do the changeover I was going to put an arb up front aswell.
So parts list for me
91 to 97 4.88 ratio gears front and back
diff carrier case from a 93-97 rear diff w/ oe locker
Arb air locking differential (front)
air compressor.
Montocr thanks for the offer. The only thing that has me up in the air about doing this myself is installing the arb and running lines etc. I thought about just taking to Randy's ring and pinion and being done with it.
Slee sent you a mail to your sales e-mail address
That being said while I do the changeover I was going to put an arb up front aswell.
So parts list for me
91 to 97 4.88 ratio gears front and back
diff carrier case from a 93-97 rear diff w/ oe locker
Arb air locking differential (front)
air compressor.
Montocr thanks for the offer. The only thing that has me up in the air about doing this myself is installing the arb and running lines etc. I thought about just taking to Randy's ring and pinion and being done with it.
Slee sent you a mail to your sales e-mail address
- Thread starter
- #5
sleeoffroad said:
How much of an increase in RPMs did you inccur with 5.29s?
Pskhaat
Tourer
3rds needs to be obtained from an 80?
sleeoffroad
Supporting Vendor
I did not run 5.29's. I ran 4.88's.
Scott, the 100 rear R&P is not available. But you can use some 80 series parts and a 80 series R&P to make it work. Rear axle shafts are 32 spline. Carl did his with e-locker, I did mine with a hybrid ARB using parts from a 80 and 100 ARB.
Scott, the 100 rear R&P is not available. But you can use some 80 series parts and a 80 series R&P to make it work. Rear axle shafts are 32 spline. Carl did his with e-locker, I did mine with a hybrid ARB using parts from a 80 and 100 ARB.
gear change
I run a 305/75/16 with my 4.88's. With a 35" or bigger 5.29's wouldn't be a problem on the highway. 4.88's and 35's puts you right about stock rpm, but I agree with christo and feel they run better a little lower geared. Oh and I am at Randy's
I run a 305/75/16 with my 4.88's. With a 35" or bigger 5.29's wouldn't be a problem on the highway. 4.88's and 35's puts you right about stock rpm, but I agree with christo and feel they run better a little lower geared. Oh and I am at Randy's
- Thread starter
- #9
sleeoffroad said:
I re-read the post and realized that now..all this gear talk has made me giddy
- Thread starter
- #10
montocr said:
Sounds good. montocr I will send you a PM and see what its going to take to get the ball rolling.
hoser
SILVER Star
I've been gearing up to do this mod as well. Just trying to decide between 4.88's and 5.29 for my 35's. I think 4.88's on the 5-speed tranny (A750F) would have been the best combination though.
As for calculations (I hope my math is correct):
Stock ('98-'02)
R&P 4.3
Tire diameter 31.3"
Auto Transmission Final Gear 0.753
RPM @ 75mph= 2607 RPM
4.88's with 35's @ 75mph = 2645 RPM
5.29 with 35's @ 75mph = 2868 RPM
So, the 5.29's will turn 223 more RPM @ 75mph than the 4.88's. It is also 261 RPM more than stock gears and tires. Hmm, what to do?
Edit: One more calculation: 4.88's with 33" tires @ 75mph turns 2806 RPM.
As for calculations (I hope my math is correct):
Stock ('98-'02)
R&P 4.3
Tire diameter 31.3"
Auto Transmission Final Gear 0.753
RPM @ 75mph= 2607 RPM
4.88's with 35's @ 75mph = 2645 RPM
5.29 with 35's @ 75mph = 2868 RPM
So, the 5.29's will turn 223 more RPM @ 75mph than the 4.88's. It is also 261 RPM more than stock gears and tires. Hmm, what to do?
Edit: One more calculation: 4.88's with 33" tires @ 75mph turns 2806 RPM.
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Pskhaat
Tourer
I think, if you're gonna go the route and $ for gears, go all the way, do 5.29s. Eventually, you'll want 36+" anyway. I'm serious, if you're gonna pony up, do it the whole way.
What's the dire need for 5.29's? The truck is powerful enough, loaded and with 4.3/4.1. 4.88 at stock would be awesome. 5.29 will cut mileage, lessen your on-road ride quality, add noise, etc.
I see 5.29 being awesome for a dedicated trail rig...though how ya gonna fit larger tires without trashing the truck? (Body lift, etc)
I see 5.29 being awesome for a dedicated trail rig...though how ya gonna fit larger tires without trashing the truck? (Body lift, etc)
Pskhaat
Tourer
I don't disagree with the appropriate 4.88s for the 35s. Just that how long will you want to run 35s? Sizes on average are going up and up over the years. 5+ years down the line you want to run 36s or 37s as I predict many people will be doing with their 100s, you may have wanted to go to 5.29s.
When I regear my 80 (which is like 10 years overdue) I'll do 4.88s from the 4.11s, not 4.56s, it just isn't worth the gear change $ to get only 10+% difference. 4.3->4.88 is only 13% difference (is that worth the $?). 4.3->5.29 is 23%.
I have not run the $s on fuel consumption vs. cost of gear change though.
When I regear my 80 (which is like 10 years overdue) I'll do 4.88s from the 4.11s, not 4.56s, it just isn't worth the gear change $ to get only 10+% difference. 4.3->4.88 is only 13% difference (is that worth the $?). 4.3->5.29 is 23%.
I have not run the $s on fuel consumption vs. cost of gear change though.
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3fj40 said:
Yes, though an 80 having a solid axle leave the door open to larger tires. Right now, nobody has a solution for the 100's IFS. What size lifts will there be in the future? Who knows. You might 5.29 the thing and be stuck for years?
- Thread starter
- #16
ShottsUZJ100 said:Yes, though an 80 having a solid axle leave the door open to larger tires. Right now, nobody has a solution for the 100's IFS. What size lifts will there be in the future? Who knows. You might 5.29 the thing and be stuck for years?
Not sure if you would call it stuck. According to the math 5.29s and 35s are only a little higher than 4.88s and 33s.
exactly
yes
yes
hoser
SILVER Star
I am fairly certain that I'll be staying with 35's. They are a tight fit already. To run 37's, I'll have to mod my existing sliders, mod my RR bumper and do a 3" body lift. I realize the 100 isn't a rock crawling rig and there is little need for such a large tire.
Yes, 4.88 is a good match to bring the gear ratio back to stock for a vehicle with stock weight. But now it has wheels that are each 60lbs heavier and the entire truck will weigh almost 1000lbs more on a daily basis and even more when on a trip. Yes, 5.29 does seem high but there is nothing in between.
Personally, I feel the 4.3's make the truck a dog and I feel bad for the transmission. If I was on flatter land, it might be okay.
Yes, 4.88 is a good match to bring the gear ratio back to stock for a vehicle with stock weight. But now it has wheels that are each 60lbs heavier and the entire truck will weigh almost 1000lbs more on a daily basis and even more when on a trip. Yes, 5.29 does seem high but there is nothing in between.
Personally, I feel the 4.3's make the truck a dog and I feel bad for the transmission. If I was on flatter land, it might be okay.
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bull said:
4.3 STOCK
vs
4.88 and 35"
That's within 1% of the stock gearing. A perfect match.
hoser said:
You know what? I've always agreed with this until my last mod to the 100. Now that I have the same articulation in the rear as an 80 and am within 2-ish inches front articulation, my 100 feels just like my 80 on the obstacles. No crap! No reason to lie. I have 2 80's for gosh sakes!
I had to buy another 80 because I have to have an 80 too. My '93 was aged and poopy. My '97 Lexus is so much nicer I'm glad I have it...HOWEVER....since that recent improvement was made to my 100....if I'd a known how close it now does on the trail to my 80, I'd a never bought the Lexus. What would I have done? Probably will now be my next project, 2 options:
1. Buy a new or newer 100 and swap all my current parts to it and lock it up. Then cut frames and shorten my current 100 to make a rock crawler. This option allows me to have a newer blingmobile.
2. Keep my current 100 the way it is and buy another 2001+ and cut and modify it as a crawler with lockers and bumpers.
I'd make certain the bumpers were no longer than the body. The 100 is now a rock crawler if you build it as such. Amando's is the closest setup to this and he did a super job. The only improvments I can see to his are:
frame shortening to accomodate tucked-in bumpers (needed!)
2000+ (so TRAC is there)
N74L shocks (needed!)
Some trimming for 36-inch tires
