change fron 3:07 to 3 :55

[dobbs571]

what I have is a 92 4.0L 5 sd D30 and D35 with 3:07 gears and went from 225?70/R 15 to 235?70/R 15.Its drove to work and around town most of the time some interstate driving about 30 to 80 miles . I need to replace the pinon bearing in the rear seal leaking been replaced twice and bearing making a noise. Has any one changed to 3:55 from 3:07 and did it help. Seem they are not hard to get a hold sence all Autos had them.

 

[lesslimited]

When I upgraded the axles in the wife's jeep, I put her originals in my 94, which is also a 5 speed. It made a very noticeable difference in acceleration and all-around torque, and the 29 spline 8.25 is also a nice upgrade from the D35. Highway mileage may have suffered a bit, but I don't do much of that, and I average around 17mpg around town, driving it like I stole it.

If the donor has a compatible speedo gear, grab that too, and your speedo should be pretty close with stockish tires.

 

[dobbs571]

Ok I have been think verry hard about doing this I fig 3:73 would be too hight and hurt my milage and I domt wheel it so no need to have low gears.

 

[foxwar71]

I just swapped a 8.8/HP30 with 3.55's into my 95 5spd with 225/75/15's. Its made a big difference off the line and going thru the gears. I like it!!! :thumbup: My highway rpm's around somewhere right around 2500rpm at 73mph. Netting me some great results coming back on the last trip, knocked out a section of highway at 26.67mpg :greensmok


I also plan to upgrade to some 30/31's so the extra gearing will do nicely to help.

 

[dobbs571]

Ok thanks finding gears from an auto should be easy I have seen verry fu Cherokee with 5 sp in them. Looked on Ebay but to high priced come on 150 for used 3:55 maybe for both D30 and D 35 but not one. I can buy the whole Jeep for that price LOL

 

[Johnnie Walker]

If you plan to go around 31 or above, I would get some 3.73s at least. Find a wrecked XJ with an auto and pull the axles.

 

[dobbs571]

I dont think i will go that big 235 are at 29in and a weck is what I am looking for are some one that has changed to taller gears and has every thing laying around .

 

[O-Gauge Steamer]

I ran 4:11s on my 97 with the 5 speed ans 32's. Worked just fine. If 3:55s are all you want, save some money and swap axles out for JY ones. Far less expensive than new gears, install kit, bearings... You get the idea.

Only caveat is ASB. If you have it, grab the correct axles, ones with tone rings.