Hello,

1987 240DL sedan with 60K miles, original suspension, the rear end is a bit sagging. Towed my boat for 400 miles - the first time towing with this car. Got up to 70-75 mph no problem. When driving at about 55 mph, and sometimes 70, sometimes uphill, sometimes downhill, sometimes on flat, basically at random intervals, I would get a decent shake in the steering wheel. Can this be tranny/engine related at all? Or is it just because I have about 700 lbs attached to the hitch and the front end is too unloaded? The hitch extends aft pretty far too, not abnormal but not like the new euro Volvo hitches. The load on the hitch ball is not high - I can walk around with the trailer tongue in my hands.

Without towing the car drives very smooth, no steering wheel shakes at all.

I am getting new rear springs which I hope will solve this issue but for now just want to make sure I am not punishing the engine and tranny bits.

As to the new springs, the car is primarily for towing the boat on the East Coast USA. So should I get IPD HD springs for sedan, or standard springs for a wagon? I understand wagon springs fit on sedan? I also saw on the web someone try HD wagon springs on a sedan and the guy said they were way too stiff. I am leaning towards HD sedan springs and Boge Turbo shocks in the back, unless you tell me the standard wagon springs would carry the weight better.

Thanks a lot, as always.