I ain't made 'o' money, so which would be a better buy, a d70 with locker or d80 stock?

 

What are you using the truck for. The D80 is a lot stronger so if you don't need the locker, I would go for that. In really tough traction conditions, there is nothing like having a locker but if stay away from the deep mud and sand, then I would go with the D80.

 

I just beat it around town and to and from work. Occasionally I pull heavy.

 

I'd recommend the 80. the old 70s are about the same strength as the new 80s and the new 70s are about like an old 60, maybe a little better, basing this on spline count of the axles. The 80 rear does cost you a little clearance that is why I run bigger tires but they are strong. I think the ring and pinion are very much tougher on the 80 than on the 70.

 

That sounds like a good application for the D80 then. Even if you don't need the extra strength most of the time, it doesn't sound like you need the locker either. All mechanical lockers, including detroits, have some undesirable road manners. They also result in lower mileage and increased tire wear.

 

Looks like the D80 had the same size spiders and axle diameter as a D70, so I am ordering the Detroit Locker today or tomorrow with new carrier bearings.... It ain't cheap... looking at $630 for the locker plus shipping.

 

If you tow heavy, consider the road manners of the Detroit, especially in the rain, snow or ice @ 7000'. Go to reiderracing.com and read, they have some good info on differentials. For better road manners and still good traction, a good posi could be a answer. A 70HD differential will fit in the 80, you will have to drill out some holes, easy to do.

 

Thanks, I'll read that. This last diff was supposed to be really tough, but I spit the spiders out just the same. I think I need to get a rear that is spiderless.... but I'm still "open" to suggestions!