Charlee, I tow a 93 Nissan SE 4WD pick-up, four wheels down, transmission and transfer case both in Neutral, towes like a dream. Little heavy (almost 4000# so I need aux braking system. Have towed this vehicle behind a 460 CID Ford/John Deere power train, a Ford F53 V10 power train, and my current DP. All have worked well.
Owners manual limits speed and number of miles when towing all wheels down, I have ignored that since the vehicle was new, now the vehicle is long time out of warranty, have never had any mechanical problems caused by towing in this manner, Generally travel at 65 MPH or less, have towed it for about 25K miles in all the years and its still going strong. I do change my differential and transmission/transfer case lubricates IAW owners manual.
"Those who stand for nothing fall for anything"
2008 Newmar VTDP - 3330 - ISBXT 350 Spartan NVS
Toad - 2013 Mini Cooper S or 93 Nissan 4WD PU
FMCA F113720, NKK 18573