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Discussion Starter · #1 ·
How would a first gen do in a truck pull IC and non-IC? Was thinking of signing my 89 up for one @ a fair.

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Bare with me just a little. Your running 3:08's for gearing. You can cover up the lack of gearing by using low range in the transfer case.

The main problem is if you bend one of those axle housings your truck will be down or limping around till you find another one. A CTD does have the power to bend them. I have already replaced the rear axle for that problem. I have another front axle in the garage for the same reason. I bent my front axle last spring. All I was doing that time was hauling a couple of 1800lb round bales of hay. I was going up a hill in low range threw 12" of snow and using a lot of throttle. The front axle started making noise. When I tore it down I found the housing bent. :(

It took me 6 months to find the dually rear axle and the front housing I found took over three months.

3:08 axles are kind of hard to find and are not cheap when you do. What I had to pay for that dually axle would put everyone into sticker shock.

If you had 3:54's I would say go for it.
 

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Discussion Starter · #3 ·
How hard would it be to swap for 3:54's?
 

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The d 70/71s have a weak pinion they break pretty easily, dont ask me how I know. But if you do pull you wont win it, if you start bouncing let out, start out in low side 1st and once you get the rpms up and the sled moving try shifting to 2nd when it starts luggin shift back to 1st
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How hard would it be to swap for 3:54's?
You would need to replace both axles assemblies. Then you would need a new speedo reducer box for the 3:54 gears.

With your truck being a SRW I bet it wouldn't be hard to find someone that might want to swap axles.
 

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Discussion Starter · #6 ·
What are the pro's and cons of 3:54's and 3:08's?

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Pro's on the 3:54's. Anyplace that calls itself a parts store can get you parts for that series of axle. All housings are the same from 3:54 and up gears. The only difference is the widths for different tire combo's. The 3:54 carrier will accept gears up to 4:88. Above that and you need a 4:88+ carrier. Con's none.

Cons: 3:08's axles are Dodge only. No other MFG used this gear ratio. The housing, R&P,carrier are specfic for that combo only. No aftermarket support of R&P's, carriers. You can use the spider gear replacement lockers. The only LS is from Dodge no aftermarket support on this item. Dodge still has them in stock. Pro's: Good road gears.

With you truck being a 727 nonOD trans a set of 3:54's will drop your top speed to around 60 MPH or so.

If you rear axle doesn't have a LS in it which is most likely. You might not even move a sled due to your right rear tire spinning. You need both rear tires pulling for that sport.
 
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