Story and photos by Richard Ehrenberg. Copyright © 2008 Mopar Action. Used by permission. For muscle car action, read Mopar Action!
Like, wow, man. A few issues back, we showed you how to swap Grant’s new look-a-like Tuff steering wheel onto any muscle-era Mopar for pocket change. This relatively simple tech article (by M.A. standards) unleashed a torrent of pent-up steering-related tech questions. Truthfully, we’ve become a tad tired of keypunching all those answers, hence this article. What we’re gonna do here is not any particular swap or upgrade. Instead, we’re gonna go “broad spectrum,” passing along a lifetime of steering-related hints, tips, and tricks. Many of these fall into the low-buck/no-buck category that has been our stock in trade for 20 years.
One more caveat before we get into the heavy-breathing exercises: Everything that follows is specifically for vehicles equipped with Chrysler-built steering, primarily 1962-up. Therefore, Dodge pickup trucks, which had Saginaw (GM) steering, are excluded. (Not that these are necessarily bad, we’re just not Saginaw box mavens.) Saginaw pumps, however, which were used heavily across the board starting in the late ’60s, and became universal by 1977, are included (and are the class act in PS pumps for Mopars). B-vans, through 1993, are also included.
Due to space constraints, we can’t steer all this info into just a few pages, so we’ll save some of the good stuff, including most manual-steering info, for the next issue. (This also helps guarantee our paychecks for at least one more go-round). At that point, we’ll also get into bump-steer, and pass along some coupler and column tricks, too. And, no, Vern, we won’t get into linkage slop. If you can’t find a beat tie-rod end or bad idler arm, go back to your Toyota—or read Mopar Muscle!
Stay tuned. Regular readers know M.A. gives you the most for your tech nickel. Still.
Power steering boxes, ’62-up, came in 2 basic flavors: Left, the large-sector box, used on C-bodies, B-vans, and everything after 1972. The small-sector box (right) was used on virtually all the muscle-era cars. They can swap as long as you use a matching pitman arm. See the matrix (right, above) for “swap meet gold” dimensions. Use this for identification only, splines are notoriously hard to measure accurately. Lost (or boogered) the oddball pitman nut and lockwasher? Think: Bouchillon!
This factory exploded view pretty much explains why we advise leaving power chuck rebuilds to the experts. One thing you can do yourself, however, is to change out a leaky sector shaft pressure seal (called out in red here). The factory spec’d all manner of Miller special tools for this. Ha! Check this: In the car, remove the pitman arm, pry out the lower seal. Remove the snap ring and retaining washer. Start ’er up. Turn the wheel against the stop—hard—in either direction, with engine revs at a fast idle. Blam! Thar she blows! Just carefully tap the new one in, then reinstall the washer and clip, then the dust seal. Done in 15 minutes. (OK, yeah, another 15 to clean up the mess.) Thanks to Randy Bouchillon for this tip.
I remember it as if it were yesterday; I had spec’d out a daily driver 1971 318 Duster for my first (of many) mothers-in-law. 3.23 SG, manual discs, HD suspension, E-70/14 tires, etc. In short, it was a performance car in every respect except the 3 engine. They asked me to drive it home from the dealer, and my mind was blown. I expected good handling and braking, sure. But the steering—that was another matter entirely. It was precise, with great feedback, and none of that feathery “tiller” feeling that I've grown accustomed to in Mopars, even brand-new recent performance cars. After a few miles, I had to stop and peek under the hood; to see what the factory had changed so radically in the steering system. To my surprise, I saw nothing new. The same pump, box, lines, linkage, etc. Then I went to the dealer and poured over the parts catalog. Again, nothing had changed.
Years passed, and I went on with other things—mostly, making HP to keep the Chevys far behind in the stoplight wars. Then, in 1978, which was the tail end of the muscle Mopar performance era, my ex wanted a new ride, her green 6-Bbl Road Runner was getting a bit ratty (you can guess what became of that car.) We spec’d out an Aspen sedan, with the A38 cop package. This included a component I had never been aware of: a firm feel steering box. And, sure enough, the car exhibited the same great road manners as her mother’s Duster.
But now I knew where the difference was: The box itself. It wasn’t long before I had equipped several older Mopars with new cop boxes. While this meant some digging for new pitman arms (all ’73-up Mopars used the larger “C-body” splines), the result was spectacular.
I began to research what was really different about Firm Feel boxes, which had actually been introduced in 1975. I came up with only two facts: (1), the reaction springs were heavier, and (2) they were “select fit assembled.” This second fact pretty much told me why the Duster had been great: Blind luck in the box’s assembly.
Today we don’t have to trust lady luck. Two vendors, Firm Feel, Inc., and Steer and Gear, rebuild Mopar PS boxes to several levels of “firmness,” the firmest being even significantly better than IMOS factory stuff.
If you’re thinking “I know where there’s a junked cop car, I’ll just grab the box,” generally, forget it. Once a cop box has 50-60,000 miles on it, it’s little better than your old non-FF one. If you’re also thinking “I’ll get a cheapo rebuilt from AutoZone,” that’s another dead-end: Every “generic” rebuilt we’ve ever tried has been pretty bad. And that’s being generous. For you daring types who wanna do it yourself, yes, you can swap the reaction springs and do a home rebuild (of sorts). But there’s enough little nuances involved in steering box rebuilding that we’ll shoot that idea down, too. Most home-rebuilds do “work” but have a very lousy feel to them. (Don’t ask how we know this.)
(Left) Here’s a box’s myriad components blueprinted and ready for assembly at Firm Feel, Inc., with worn parts replaced, and Firm Feel’s firm feel Stage II reaction springs (arrows). Assembly skill and parts selection is what separates the men from sloppy steering. (Right) It takes lots of balls— 26 of ’em, to be exact, to build a fresh, tight Mopar recirculating-ball power box. FFI uses only 100% new, bearing-quality high-carbon aircraft (chromium) grade E52100 alloy steel balls.
“High spot.” These are, without question, the two most important words when it comes to steering precision in our classic Mopars. No, this isn’t the place you go to smoke weed. This term refers to the one—and only one—point in the rotation of your steering box’s wormshaft where there is zero, or near-zero play. This point is supposedly, and usually is, at a point exactly halfway between the two limits, clockwise and CCW. If your car has one of many defects which result in the car driving straight ahead when the steering box isn’t on the high spot, you'll have a lot of free-play or lash while going straight and binding at some point other than straight ahead. In other words, the steering wheel will be acting strictly in an advisory capacity. That sucks.
There are several ways this can go quite wrong. As our cars get older, and knowledge as to how to correctly assemble, check, and set up the system fades, more and more cars have woeful steering. Even worse, young Mopar guys assume “that’s the way it is.” Not true. Set up up right, these cars were as good as many new cars and better than anything else from the ’60s and ’70s. Check the accompany photos and captions for the details.
To check that all components of the steering system are lined up correctly, begin with the steering wheel pointing straight ahead.
(Top left) At this point, the steering wheel’s master spline must be at 12 o’clock, if there’s any doubt about this (maybe some idiot filed a new, incorrect master spline, or ah after-market wheel adapter; which frequently have no master spline index, was installed incorrectly), remove the wheel nut and have a look (you can see the column shaft master spline without pulling the wheel as long as you remove the nut).
Now move down to the engine compartment and confirm that the coupler’s master spline is also at 12 o’clock- Later coupler bodies have a notch that’s aligned with the master (arrow). Not sure? Pull the Coupler up a bit and check the splines on the boxes wormshaft. Don’t guess.
At this point, the wheels should be straight ahead and the amount of visible thread approximately equal on all four tie rod ends. If not, your front end alignment guy did a “workaround” because something’s not right. Possible problems are an incorrectly assembled poi coupling (inverted, more on that next issue), the aforementioned steering wheel installation snafu, frame, chassis, or linkage damage, or, more common than you might think...
...a twisted chuck (steering box) sector shaft. Nasty!
Power steering requires— duh!—power steering fluid. Not ATF! Keeping the fluid cool is also important if you want long component life, it can also help reduce low-RPM assist loss by maintaining fluid viscosity. Generally, the factory provided coolers only on cars destined for heavy-duty/fleet operation, and on cars with steep rear axle gears. The junkyard is full of small coolers which are easy to install via a bracket mounted to the pump, and plumbing couldn’t be easier: Just splice it inline in the return (low pressure side) hose.
(1) It’s not a bad idea to flush and change the fluid every couple of years. Do this by disconnecting the return hose from the pump, capping off the pump nipple, and sticking the hose in a bucket. With the engine at the lowest idle RPM, keep filling the pump until at least a quart of new juice has replaced the old. The factory fluid is great, yet synthetic probably has some advantages, particularly if you don’t run a cooler. Red Line’s seems to be the most widely distributed. (2) The factory used coolers on cop cars and taxicabs, and musclecars with high numerical axle ratios. Not a bad idea. They install easily, all you need is a homemade bracket attached to the pump or pump brackets, and a bit of extra 11/32” (not 3/8”) return hose. The junkyards are full of them, even 2nd-gen Neons had ’em (mounted in the airstream beneath the K-member, or buy new as P/N 5272334AD). If you get desperate, the aftermarket offers quite a few (Fluidyne unit shown). (3) One low-buck aftermarket trick seems to have some merit: A return-line fluid filter, which is an easy install—A-1 Cardone’s filter (which we found at A’Zone) simply slips into the return hose (again, 11/32” only). Sticking a large magnet on the bottom of the pump reservoir is another useful, life-extending idea.
The simplest, zero-buck way to improve steering feel and remove slop is a 2-minute lash adjustment. (Bet you have at least 2” of free-play at the wheel.) Yet, many guys are afraid to touch this, or, even worse, have no idea how to do it properly. Done wrong, it can produce a totally numb steering system. It is really a cinch to do right. We’ll make you an expert.
This factory cutaway clearly shows the position of the sector lash adjustment (and locknut), just forward of the valve body’s return nipple. But how, exactly, do you adjust the lash, to eliminate wheel freeplay? Yeah, how?
Keep the wheels on the ground up and the engine idling; be sure the wheels are dead-ahead, as indicated by the master spline on input shaft (and/or notch on OEM coupler and stripe on OEM steering shaft) at 12 o’clock. THIS IS VERY IMPORTANT- It puts the gears on the “high spot.” This also assumes nothing is bent, twisted, or otherwise mucked. On just about any Mopar except slant sixes, you'll be smart to be wearing some heavy leather or asbestos welder’s-type gloves you'll be right by the exhaust, grabbing the coupler body.
It was tricky to photograph the details of what you’re doing on an actual vehicle, so we built this mock-up for clarity. Loosen the locknut (1). Start the engine. Reminder: all three wheels should be straight ahead (i.e., do this last, after your front-end alignment.) Now rock the coupler (2) back and forth about +/- 5° of rotation (from the dead-ahead, 12 o’clock position) while observing the movement of the pitman arm (4). Tighten the adjusting screw (3), which may be slotted or hex-recess [Allen] depending on the box’s year of manufacture) until any observed slop just disappears. Then re-test, this time rotating the coupler even less. The goal is positive pitman movement, however slight, for any sector rotation. Once that point is reached, tighten the screw just a kitty hair more—maximum 5° (This assumes a well-used box; on a new or nearly-new box you'll want a bit more preload). Now, tighten the locknut while holding the screw in position. Now’s a great time to check for any slop in tie rod ends, the pitman arm ball end, the idler arm (both ends), and even the LBJs (which usually don’t result in much static steering slop; vehicle weight keeps the ball firmly in the socket.)
Everybody knows that a lousy front-end alignment (especially unbalanced camber. L/R) makes your Mopar pull or drift to one side. But did you know that a simple incorrect adjustment to your power steering gear can cause the same symptom? It’s true, and, when seriously misadjusted, can make the pull so strong that even Schwartzenegger (The Governator) would be hard pressed to keep the car aimed straight ahead. This adjustment will take only minutes, testing for incorrect adjustment is even faster. Check the pix for the meat and potatoes.
(Left) Place the wheels in the dead-ahead position, engine off, wheels off the ground. Now start the engine while observing the steering wheel. There should be zero movement of the wheel as the engine starts. If there is the slightest movement, the valve body needs to be adjusted.
To adjust, loosen the valve body screws (arrows, A, until they are finger tight, then snug them up a skosh. Tap the valve body back (B) and forth until there is zero self-steering tendency. Two caveats here: First, if the bolts are too loose during the adjustment, fluid will spray out all over. It’s ugly. Second, if you inadvertently adjust it way off, the wheel can violently turn when the engine is started, so never reach for the key through the wheel. Randy Bouchillon has witnessed a broken arm this way. If you’re a blueprint-brain, you can check the turning torque at the steering wheel nut (in./lb. torque wrench); it should be identical in both directions.
Over the span of the muscle era, Ma Mopar used power steering pumps from three separate vendors: Thompson (TRW), Federal (F-M), and Saginaw, which was part of GM but was spun off and is now part of Delphi Automotive. Over the decades, only one has had real staying power, being used on Mopars as late as 2003: The Saginaw. And this is for good reason: It was the quietest, driest (external leakage), smallest, coolest-running of the bunch, and, most importantly, produced the most consistent pressure at low RPM, minimizing the dreaded “pump catch,” wherein you momentarily lose power assist during low-speed maneuvers such as at an autocross. Therefore, unless you are doing a 100-point restoration, you should be using the Saginaw pump in any build where you've decided that you want power steering.
Introduced on Mopars in 1966 (smallblock B-bodies received them first, for some arcane reason lost to history), and achieving 100% usage by 1977, the Saginaw has undergone several design changes which affect, but do not prohibit, swapability. Check the accompanying pix for more than you need to know. One small bit of trivia for you bucks-up guys: You can still get a brand new Saginaw pump from your local Chrysler dealer. Ask the man for P/N 52039489AC.
(Left) Here’s the first-gen Saginaw (left) and last (right). Despite visual dissimilarity, they are kissin’ cousins. In fact, the 1960s reservoir swaps onto the late (’75-up) pump in seconds, making them visually identical. Starting on 1980 pumps, the outlet (pressure) fitting went metric. However, the threads in the pump casting remained unchanged, so you can swap a US-thread outlet fitting into a 2003 pump. All Saginaws used an externally threaded 5/8” shaft with a Woodruff key (arrow) until 1974, after that the shafts were 3/4”, with an internal thread for the puller/installer tool. The factory never made large-shaft pulleys to use this with muscle-era brackets, but Bouchillon does, in fact, they have pulleys for almost every conceivable Saginaw combination. Here’s a hot tip that may interest you: Saginaw pumps from slant-six cars had a regulator valve (easily changed, see the FSWI) that produced about 300 PSI less line pressure. Result: Low-buck high-effort steering.
To use a Saginaw on an early car with the huge heater-hose-size return hose, you need to swap to 11/32” hose and a like-sized return fitting on the chuck. Bouchillon has ’em in several varieties (re: nipple angle).
Ditto the pressure fitting. In most cases, we’d advise spec’ing a pressure hose for your engine and a Sag pump, in a circa-early-’70s car they are readily available. If the pump end doesn’t mate to your chuck’s fitting, Bouchillon has your back.
One of the reasons for using a Saginaw pump is the ready availability of all installation parts. Hoses (not shown), brackets, puHeys—whatever you need, it’s out there. Bouchillon seems to be the one-stop shop. They even carry the hard-to-find thin-pattern pulley-mounting lock-nut and special pulleys to adapt the later 3/4” “smooth” (press-on pulley) shaft pump to early Mopars. Hoffman’s Winners Circle makes a super nice bracket kit that also includes 100-point resto-correct mounting hardware (bolts, etc.) and 440 Source has low-cost brackets.
All of our classic Mopars—1962 to 1975 A, B, and E-bodies—used 9/16” tie rod ends with 3/4” O.D. adjuster sleeves (A). For heavy-duty use, such as rally or road race, MP has always recommended welding up the gap in the sleeve. Today, however, we have many more elegant options to reduce steering tie rod flex. The lowest-buck route is simply the “bulged” sleeves (B, 7/8” O.D) supplied as replacement by most aftermarket vendors; since these fit the stock 9/16” ends, they are drop-in replacements. Next up on the food chain are the ’74-up C-body 11/16” ends and adjuster sleeves (C), also measuring 7/8” O.D.; these bolt into any classic Mopar, they were also a “random factory option” on 1976-’80 F-bodies. All of the above require a slot at least at the outer ends of the sleeves since they use pinch-clamps for adjustment locking. So the final solution is the solid sleeves (D) from Firm Feel, Inc. These use jam nuts instead of pinch clamps for locking, eliminating the slot entirely. Drag cars might get away with lightweight aluminum sleeves, but these must never be sure on the street!
Firm Feel, Inc., 2730 NW Bliss Road, Vancouver, WA 98685
Bouchillon Performance Engineering, 937 Commerce Circle, Hanahan. SC 29406
Steer & Gear, 1000 Barnett Road, Columbus, OH 43227
(800) 253-4327 www.steerandgear.com
For more from Mopar Action, click here!
Chrysler Heritage • History by Year • Chrysler People and Bios • Corporate Facts and History
Is there an error on this page? Let us know and you could win a prize!
More Mopar Car and Truck News