Steering Box Swap

 

Steering Box Swap

 

 

If you're tired of spinning your power steering equipped Chevelle's steering wheel more than 4 turns lock to lock, there's a lower cost solution than the big bucks aftermarket PS boxes. The Saginaw Model 700 power steering box installed on 64-72 Chevelles was produced in many variations up through the 90's. The desirable ratio was 12.7-1 which yields approximately 2 ¾ turns lock to lock of the steering wheel. Chevelle SS's from '69 up had variable ratio steering with about that number of turns LTL but was very light effort. Rebuilt Chevelle boxes are available in fast ratio from most of the large auto parts chain stores for around $150.


A popular steering box swap in 64-72 Chevelles is the box from an 80's or 90's large RWD GM car, '83-'88 Monte Carlo, or '92-'98 Jeep Grand Cherokee. A table of the desirable boxes and much other valuable swap info is at www.chevelles.com/techref/ftechref29.html. The most popular swaps seem to be from '83-'88 Monte Carlo SS and '92-'98 Jeep Grand Cherokee. The boxes will bolt right up to the Chevelle frame but the Chevelle pitman arm must be utilized. Also, in '77 GM went to a ¾" steering shaft from 13/16" so a different rag joint is required. You can get a new GM rag joint that will fit, PN 7826542 but they're not cheap. You can get a new one from Lee Mfg, www.leepowersteering.com for around $80, or use one from a '77-'82 Chevy/GMC 2wd or 4wd pickup, '83-'86 2wd only pickup, '77-'78 Camaro, Firebird, or Nova, or '79 Nova. On '64-'66 Chevelles some slight modifications to the steering shaft flange is required. Go to the previously mentioned chevelles.com tech ref link for info on that. In 1980 GM went to metric O-ring hose connections on the boxes so to keep the Chevelle pump you must get box fitting adapters from Lee Mfg ($8) or a pressure hose from an '85 Olds Cutlass Supreme with 307 V8 and a return connection from any '80's GM rwd car.


To swap pitman arms you'll need a 1 5/16" socket. I could only find one in ¾" drive so I had to get a ¾" to ½" drive adapter. A pitman arm puller is also required and you can borrow one at any Autozone store. I also needed 3 ft long pipe "cheaters" to fit over both the pitman arm and the breaker bar to get enough leverage to get the pitman arm off.


I swapped in a used box from an '85 Monte Carlo SS in my '69 Malibu and like it a lot. The MC SS boxes are high effort though which I'm not particularly fond of. I used the rag joint/hose fitting adapter kit from Lee Mfg (approx $100 incl shipping) but if I had it to do over again would probably just get a rebuilt Chevelle box in fast ratio. On second thought maybe not. I just read on-line of someone getting three bad rebuilt boxes in a row from a large chain store, the N one.


You'd be surprised at how much a faster ratio steering box improves the driving experience, so it's definitely worth the money and time to make the swap.