I've got 3.54s in my 91.5 W250 w/Getrag and plan to switch to 3.07 axles. I don't expect to do a lot of towing, but some. Just trying to squeeze a mile or two more mpg and make it quieter on the highway. My concerns are: Is this gearing too tall to tow? Does regular drivability suffer? Are there any inherent weaknesses in the 3.07 axles? Nobody makes the gearsets anymore, but are wear parts available for the Dana 61 and 71 axles? I plan to keep this truck a LONG time. Any sage advice? Thanks.

 

could always look into a gearvendors.

 

I think if you can get the load rolling, you should be ok with 3.07s. 4th gear with 3.07s is real close to 5th/OD with a set of 4.10s. If you have plenty of power now, you should do ok with the higher gears.

Bearings, clutches (LSD), etc, are still available. Just not the gears themselves.

 

That's a big change, IMO..... based on my going from 3.54 to 3.20 (due to 35" tires).
I would never do it w/ an automatic, but with a manual, you may be able to live with it?
If you're at stock power I'd be very reluctant.

RJ

 

I have the 3.07/getrag combo and love it. My truck pulls so hard and fast, especially on the top end. Pulling a trailer is not too bad. I pulled a 28' travel trailer with no probs, just start out in first. Of course, I am way above stock power.

 

With having had said that...If you don't have any mods on your truck, make sure to downshift and don't lug the tranny..

 

Philip's '93 with a 518 came form the factory with 3.07's, and from what I recall he loves them.

 

i have a 3.07 :-)

 

Are you planning on swapping the complete axle or just the guts?

Reason I ask, I have a 3.07 rear end too sitting under my parts truck.

 

The concern I would have about a getrag/3:07 combo is the trans gearing. A getrag has a big hole in the gearing between 2nd and 3rd. With 3:54's it just a little annoying but you can live with it. With 3:07 gears that hole is going to be massive. Which is going to be even worse when towing.

A NV4500 has the same big hole between 2nd and 3rd. So it isn't much better option as far as gearing goes.

The only stick shift I would want in front these tall gears is a NV5600 or a G56. Both of those trans has better gear spreads without holes in them.

Untill I find a 6 spd in my price range. I'll stay with an auto with these gears.

Timmy you can't swap the guts. A 3:07 has its own axle housing. The 3:07 R&P won't fit any other housing.

 

this old man wishes he had a good spare for his 90. if the rear goes i have to change both ends and i love the 3.07 with my auto.

 

jughead. I like my 3:07's also. When ever you see a 3:07 axle listed at a reasonable price. Buy it for spare parts.

I have spare R&P's for both ends of my truck.

 

I can't imagine a raggy with 3.08's unless you have a 4,000rpm governor spring in there. Without significant upgrades the 2nd-3rd wide gear spacing would be a black hole. Incidentally, the NV4500 has MUCH more even gear spacing.

 

There are a few people on here with 3.08s, 35's, and 5-speeds I think. I can't remember who they are tho. They said they get good mileage with em. I would love to drive one just to see how hard it is to get em moving. I bet they don't have a problem with wheel slip.

 

and no overdrive