gearing

[frank334]

i have a '58 CJ5 with 134 ci engine, it currently has 5:38 gears. i would like a llittle more top end speed. any recommendations?

 

[tarry99]

i have a '58 cj5 with 134 ci engine, it currently has 5:38 gears. i would like a llittle more top end speed. any recommendations?

Frank, you could surely put in a taller ( higher) gear like a 4:88 , 4:56 or 4:27's they would all help your top end speed but you would have to change both the front and rear end gear sets..........not cheap about $250-$300 a set plus labor.

Best thing to do and I'm assuming that you still have a Dana 18 Transfer Case with the offset drive is to find a Warn Overdrive that plugs right into the accessory port in the back of the Transfer Case ...........drive shaft length stays the same and the Warn will give you a 25% reduction in all forward & reverse gears............
At a 25% reduction in high gear with the 5:38's that changes your final drive ratio to 4.03..........quite a change. There are gear ratio calculators on this site or check the internet........You will also need to know what tire size you have to calculate Speed.
One last thing that little 4-banger will probably not like being in that tall final gear unless it is wound up some ..........RPM wise that is.
Herm the Overdrive guy in Washington state sells them.

 

[Saddle Tramp]

There are a few things to consider. Having the original I-4 motor (assuming that it is) means it puts out about 75 hp at best. Tire size becomes critical which may have something to do with why there is such low gearing already installed. However with the Spicer 18 you have two options that may help. As mentioned before, an overdrive will go a long ways to reducing high speed RPMs but also a Teralow kit can be installed to lower the low range of the transfer case. This opens the opportunity to put taller (numerically lower) gears in the differentials which will also lower high speed RPMs but due to the lower transfer case gearing from the Teralow kit it is possible to maintain a reasonable crawl ratio.

Having said all of that, the mighty but little 134 only has so much poop to give. Try This: http://hermtheoverdriveguy.com/