Mustang 2 question.

[reborn55]

Getting ready to replace power rack and pinion on our 48 Chevy sedan delivery(leaky seals).  Need a quick crash course on identifying what year will work.  I think it is the early vintage due to the mounting holes being 16 inch center to center and the short steering shaft.  Would like to go to a later year--does it make any difference--worth the trouble to try as I think the mounting holes are at a different spacing.

Another note--trying to get rid of shimmy/vibration problem.  When I test drove the car, it had a little shimmy in the wheel at about 65-70 mph.  PO said it needed new rotors.  I had the Boyd 17 inch wheels rebalanced, went ahead and had driveshaft rebalanced, new trans mount, took rotors in and had them turned--have one out of specs so I need to get new ones.  Put it all back together to go to cruise past Saturday(with the old rack).  Shimmy is so bad now it will chatter your teeth.  Tried wheels and tires off the 55 Sunday morning with little or no difference.  everything else looks OK.  Shimmy/vibration kinda comes and goes but needs to get fixed to bring some kind of peace in the household--wife wants to drive to Louisville and hopefully back.  I am thinking the rotors are probably bad--just get frustrating when you try to correct a problem it only gets worse.  Thanks in advance for any help.

[UGLY OLDS]

Ken..Been following this "adventure" on another board..( I lurk a lot   ) .. Check all the u-joints & couplers in the shaft from the input on the rack to the bottom of the column...A little play "here & there" can REALLY add up & just gets more pronounced when you get a little shimmy...Also..Did you ever get this car aligned???  :?:  :?:

[enjenjo]

Having gone through the same thing on my 47 Chevy, I can sympathise. I changed from the early rack to the later 79 to 89 style rack, using one for a Tbird. The hole for the right side is 1/2" different, some cross members can be modified by slotting the hole, others need a new mount installed.

It slowed the steering down a bunch, but it was still darty. I increased the caster to 6 degrees, and that cured it.

[reborn55]

Thanks guys.   Olds--you a lurker--hard to believe.  I do it a lot.  
Going to start on replacement of the rack, lower ball joints, and rotors tomorrow.  Will get it aligned before Louisville if this replacement of parts cures the shimmy problem. If not I will bury the car and take a year off and forget about cars--or at least that is how the wife says it.

Car actually handled and steered pretty good when wife drove it home--only got worse when I tried to fix things.