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4.88 and 33's feedback

O

oldskooldubbin

NAXJA Forum User
Location
WA
I have read through the gearing threads. Seems most would say go 4.88 with 33's for the trail. The question I never really found a answer for is. With a 4l aw4 4.88's and 33's what rpm do you run at 70mph? I drive back and forth 100 miles or so at 70 to 75 most weekends so this is important.
 
70mph to 75mph = 2609rpm to 2795rpm

From what I've researched, best fuel economy is supposed to be between 2110rpm - 2640rpm. Since mine is a DD 95% of the time and CA freeways cruise in the 70mph - 80mph range, I decided to stick with 4.56's for my 33's.

Check out this calculator:

http://www.grimmjeeper.com/gears.html
 
Sounds about right.

I drove on 4.88s and 33s for a while.

Was an awesome combo with plenty of get-up-n-go and still enough to cruise at 70 on the highway. 75 was kind of pushing it (felt like it was starting to wind out), and I only ever did short sprints to 80.
 
A freind of mine is running 4:10s in his rig on 33s and it feels like its got a fair amount of power and not bogged down too much hoever I'd go 4:56 IMO 4:88 is too much gear unless its not highway driven.
 
Yea I am hoping to hear from someone whole has this setup in a rig that does see highway time. I am already leaning more toward 4.56 though.
 
id do 4.88's

5.38's and 35's is AWESOME

highway driven 400 miles to the trails, not over revving, still getting around 20 mpg
 
4.88's and be done with it!!! Youll never look back, trust me. i have 4.56's with 35's and have been with colin (moparmanic) with his 4.88's with 33's and 35's. i really think the difference is barely noticeable. a little bit more rpm's, but the 4.0 doesnt care. i would/have run mine all day on the highway doin 2500-3000 rpm's at 70-80 mph without a second thought.
 
If there is even a thought of going to a larger tire at some point, go with the 4.88's. Otherwise I would go with 4.56's
 
Johnnie Walker said:
If there is even a thought of going to a larger tire at some point, go with the 4.88's. Otherwise I would go with 4.56's
Click to expand...


I agree...for now I have 31's and I plan on going to 33's here next year...and maybe bigger and bigger, but I know that if you go w/ a 4.56 you are going to be limited to the tire size in the end, The 4.88 is about endless and it poops and scoots out of the hole a lot better! If your going to re-gear do it once....go w/ the 4.88!

and tell me how it works because that's what I plan on doing here in a minute along w/ a locker :)
 
I just got back from a trip last week, around 750 miles round trip. I run 33's/4.88's/AW4. I do not have a tach so I can't tell you what RPM's I was running. I can tell you that I do really like the setup. I think it's a great combo. I averaged 16.5 mpg for the whole trip with the cruise set on 68mph.

Several years ago, I ran 30's/4.10's/AW4 and absolutly loved it.
 
Although mine is not a dd, I do drive it on the highway often. I normally run 65 at about 2800. If I need to pass, it's got enough left to get up to 80 (3500ish) pretty easy. My heap is an 87 and by no means a race car, and I don't drive it like one. Even if I had higher gears, I wouldn't drive it any faster.

just my .02
Jeremy
 
thats what ive been looking at getting. i have 33's right now on 3.55's and its a dog on the highway. its my DD and i drive across the US quite often. so i was worried that 4.88's would be too much. i do plan on eventually going to 35's though when my 33's wear out.
 
Can't recall how many times I've addressed this question, but I highly recommend 4:88's and 33's.

My current XJ (owned 3 with a variety of tires and regearing) is daily driven (2+ years) on the freeway and wheeled on the weekends. I commute approx. 60-80 miles a day and average 18mpg freeway, 2000 XJ/4.0/AW4

The 4.0 purrs along happily at 2700rpms at 70mph, which is not even close to redline (5000 rpm). Low end power is great and I can pull hills without the AW4 jumping between OD and 3rd gear.....a very common problem for folk who wuss out and go with 4:56's. This hunting between gears in not only annoying, it make the trans work harder, creating more heat and in a very inefficient use of power. If you live where the Earth is perfectly flat, 4:56s may be OK, the first hill or steep freeway overpass will send your rig hunting for the right gear with 33's.

Do it once, do it right.
Listen to those of us who have been there, done that. I contend that folks with 4.0/AW4/ 4:56's and 33s who tell you its a perfect setup, have never driven a rig with 4:88's, or are still trying to convince themselves that they made the right choice. :confused1
 
XJEEPER said:
Can't recall how many times I've addressed this question, but I highly recommend 4:88's and 33's.

My current XJ (owned 3 with a variety of tires and regearing) is daily driven (2+ years) on the freeway and wheeled on the weekends. I commute approx. 60-80 miles a day and average 18mpg freeway, 2000 XJ/4.0/AW4

The 4.0 purrs along happily at 2700rpms at 70mph, which is not even close to redline (5000 rpm). Low end power is great and I can pull hills without the AW4 jumping between OD and 3rd gear.....a very common problem for folk who wuss out and go with 4:56's. This hunting between gears in not only annoying, it make the trans work harder, creating more heat and in a very inefficient use of power. If you live where the Earth is perfectly flat, 4:56s may be OK, the first hill or steep freeway overpass will send your rig hunting for the right gear with 33's.

Do it once, do it right.
Listen to those of us who have been there, done that. I contend that folks with 4.0/AW4/ 4:56's and 33s who tell you its a perfect setup, have never driven a rig with 4:88's, or are still trying to convince themselves that they made the right choice. :confused1
Click to expand...


So with 33's and 4.88's are are right at 2700 at 70mph? Is that indicated because i would guess with 4.88's the speedo would read a bit fast without changing the gear. I do not plan to step up to 35's at this point cause we all know with 35's its only a matter of time before the D 30 breaks.
 
HaleYes said:
I just got back from a trip last week, around 750 miles round trip. I run 33's/4.88's/AW4. I do not have a tach so I can't tell you what RPM's I was running. I can tell you that I do really like the setup. I think it's a great combo. I averaged 16.5 mpg for the whole trip with the cruise set on 68mph.

Several years ago, I ran 30's/4.10's/AW4 and absolutly loved it.
Click to expand...
For the record, I've changed my speedo gear and according to my GPS, it's dead on.
 
I dont like this haha I CANT DECIDE! Half the people say one and the other say another. I just wanna regear! my 33s and stock gears are killling me
 
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