An aluminum D44 was used in the Grand Cherokee. From what I understand it was a POS. As for the D44 in the rear of the Corvettes, I have not heard any complaints. I think it depends on the hp/weight ratio of the vehicle and what it is used for. The Corvette and the Viper are fairly light and use IRS. The IRS D44 aluminum center section on the Corvette and Viper is rather strong because the housing does not have the stress from the axle tubes, thus smaller and stronger. A lighter vehicle with different rear axle architecture. However, add the axle tubes (as on the Grand Cherokee), more vehicle weight and different use (street rod vs. SUV)? Well, that is another story.
As for me, I already have a standard FF D60 sitting in the garage. I believe it came out of an International Scout, but it is the right width: 60" WMS to WMS. The tubes are a little thin, only .25", but I plan on adding strength with a truss (Treks Offroad) tying the center section to the tubes (I will post some pictures soon). This axle is going under my XJ. I was considering the D60 out of the SRT-10 for my TJ because I believe it has 3/8" tubes and factory support for parts (except for narrowing the axle & shafts to 60" to fit under the TJ) along with it being out of a Dodge. I liked the idea of saying, "And it has a rear axle from a SRT-10 under it."
Now it looks like I will take a different route.
Currie Enterprises Rock Jock 60 anyone?
Thanks for the info.