gear ratio info

[SoloCamo]

 

I was looking for a info site like that before. what site is that. I would love to run a v# or 2.

I was recently laid off from a dealership, but I still have my access to the internet based parts lookup system called Star Parts...that screen shot is from there. Only Chrysler employees have access... ;)

 

Not to go off topic here...but would you mind running my VIN for me if you get the chance? I have absolutely zero original info on my '88...

[tazjeeper]

 

I was looking for a info site like that before. what site is that. I would love to run a v# or 2.

I was recently laid off from a dealership, but I still have my access to the internet based parts lookup system called Star Parts...that screen shot is from there. Only Chrysler employees have access... ;)

 

Sorry to hear you got laid off.

So can I send you a vin and you can run it for me? if so that would be great.

[BLHTAZ]

Sure...send it over. PM me if you don't want to post it in public on here :thumbsup: . Can't promise that it will show a lot or that it will be 100% accurate, but I will get what I can.

 

 

And...BTW...JT, then one you sent has not had the o2 sensor recall done yet either... :rotf:

[jtdesigns]

^ :rotfl2: yeah? lol My 96 XJ has a recall on the cat, just haven't had time to take it to the dealer yet... I need to before they all go belly up don't I!!! And speaking of the O2 sensors... What if my truck falls into that recall too, and I have put another O2 on it already?? Think I should find an old one and put on it then take it to the dealer?

[tazjeeper]

Thanks a lot I will pm you.

[BLHTAZ]

Thanks a lot I will pm you.

Got your PM. I'll work on them and see what I can find for you. :cheers:

[BLHTAZ]

I have replied to the PM's received. If you PM'ed me about VIN info, please check your messages :cheers:

[1990 Pioneer 4x4]

Thanks for the info Brent.

 

So apparently I have 3.55 gears. Is there that much of a noticeable difference between what I have now and 4.10? I kinda like the drivability (road) of it now, but wouldn’t mind lower gears for the trail.

[BLHTAZ]

Yes...there will be a noticeable difference with that change. That is a 16% change from 3.55 to 4.10 and anything more than a 10% change is going to make a difference. A gear ration change of less than 10% is worthless, but depending on tire size, a ratio change of 16% may be overkill. If you are running 31's or 33's, you will be OK...anything smaller and 4.10's are just going to have the RPM's way to high.

[1990 Pioneer 4x4]

I’m running 30” tires (BFG MT’s) and don’t plan on any larger tires for the future. So, it sounds like I should probably just stay with the 3.55 gears.

[kmack]

smaller gears means less wheel rotations per engine rotation right? so when you get a bigger set of tires, you might consider getting smaller gears?

[BLHTAZ]

I’m running 30” tires (BFG MT’s) and don’t plan on any larger tires for the future. So, it sounds like I should probably just stay with the 3.55 gears.

Yeah...you'll be fine with the 3.55's for 30's :thumbsup:

 

 

smaller gears means less wheel rotations per engine rotation right? so when you get a bigger set of tires, you might consider getting smaller gears?

Yes...if you get larger tires, then you need to go to the lower gear ratio. If he were to go with 33" tires instead of the 30's then he would want to have 4.10 gears instead of the 3.55's :cheers:

[mvusse]

I have run 275/75R15 on my truck since I got it last February and think 3.55 gears with the 4.0/AW4 is a good ratio for those. Those tires measure 29", which is about what 30" tires measure. Most tires measure about an inch smaller than their size for some reason.

 

3.73 might be better, but 4.10 would be too much. And there's not a big enough difference between 3.55 and 3.73 (about 5%) to warrant the cost of regearing 2 axles.

[Pete M]

IMO, 4.10 is never too much gear. :D I think you're just worrying yourself over nothing. I've got 3.92s in my Dakota R/T and with the factory tires at 28" tall, it does just fine.

[tazjeeper]

IMO, 4.10 is never too much gear. :D I think you're just worrying yourself over nothing. I've got 3.92s in my Dakota R/T and with the factory tires at 28" tall, it does just fine.

yes pete I know someone that has 4.56's and runs a 30" tire. that jeep work's great. but it does have a 454 big block pushing almost 800hp

[kmack]

oh jeeze i got it backwards. i thought that the reg. gear was like 3-4 and then when you put it in low gears on the transfer case it would make it something like 2.5. and thats when i thought that because i have 3.07 i think, it would be closer to what my low range was and therefore, better for if i got a bigger tire. i only ever plan on going to a 30" though. so having the 3.07 is going to get me better gas mileage and less torque in the broad picture. :???:

[BLHTAZ]

3.07 will get you by with 30's, but 3.55 would be better for driveability and gas mileage. I am running 31's with 3.07's right now and hate it. I get 17-18 MPG at best when I should be getting at least 2-3 more than that. I am going to go to 3.73's one of these days when I get a job again.

[Eagle]

I ran 30s on my XJ with 3.07 gears. It was drivable on the street, but rather "doggy." Not good off-road -- the crawl ratio even in low range was terrible. The 3.73s I put in the MJ were originally bought for use in the XJ with 30" tires, and I still think 3.73 is the optimum all-around ratio for 30" tires. But that wasn't a factory ratio. If you're shopping for complete axles in a junkyard, I would favor 3.55 if it's a daily driver, and 4.10s if you do much off-roading.

[kmack]

nice good to know!