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1953 Chevy Truck Frontend Suspension Rebuild - Straight-Axle Straighten-UpRebuilding Your '47-53 Chevy Frontend From the July, 2008 issue of Classic Trucks By Rob Fortier
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There's definitely something to be said for people who want to "keep" an I-beam axle under the front of their old truck. In an era where it's commonplace to retrofit outdated chassis with modern independent suspensions, it may seem odd that anyone would want to retain, let alone rebuild, a parallel-leaf setup-and with non-power drum brakes and all, no less! Well, guess that's comparable with preferring to ride an old rigid-framed Harley over a new model that features a fully suspended rear...sometimes, you gotta sacrifice comfort for style. Unlike the motorcycle comparison, when dealing with a straight-axle equipped pickup, there's another big factor involved-cost. For many, it's a hell of a lot cheaper to simply rebuild that antiquated frontend versus installing (or often having installed) a Mustang II-style or similar IFS. And in reality, while there's no doubt a huge difference in ride quality between the two (the IFS winning that one of course), you can improve the performance of a parallel-leaf setup to a certain degree. And for someone who's used to riding a rigid motorcycle, well, let's just say even the slightest improvement will be noticeable. Same goes for the brakes and steering. The one area where limitations are extremely hard to overcome with an I-beam is of course the stance-you can only go so low before running into all kinds of trouble, period. If extreme drop is what you're after, it's probably best you go with an IFS. But, if you can live with the few inches a set of lowered springs and a dropped axle will give you, read on. We decided to give LMC Truck a call to see what they offered in the way of frontend parts for a '47-53 Chevy half-ton. As it turned out, they stocked pretty much everything we needed, including all the necessary items to rebuild the stock drum brakes, as well. As we started tearing apart the old components, though, we realized that there were a few things needed that LMC did not offer-mainly a set of spindles. For as many trucks that have been IFS'd in the past, it's amazing how difficult it is to locate decent discarded I-beam items. Luckily, a call to Bowtie Bits not only resolved that issue, but also the situation we were about to encounter with the steering arms (more on that later). Typically, an early Chevy frontend can be rebuilt with basic handtools, as there's no machining involved-that is, as long as your axle and spindle kingpin bosses aren't excessively worn. If that's the case, you may want to consider locating another axle, or better yet, stepping up to a new one like the dropped version CPP offers. We started off on the '53 by going through the main suspension first and will follow up with subsequent installments covering the steering and brakes separately.  While the frontend's stance...  While the frontend's stance on the '53 was acceptable, the ride and handling were anything but-bumpsteer, severe brake pull, and overall sloppiness are not favorable factors. Let's try and overcome these, starting with the suspension.  Generally, the majority of...  Generally, the majority of parts come apart with little to no resistance, however, depending on the type of life your truck was leading up till now, you may encounter some stubborn parts along the way. Just remember to lubricate well wherever necessary. For the kingpin caps, drilling a hole for prying them out can help save you time...and aggravation.  One possible area you might...  One possible area you might run into some resistance is with the kingpin locks (or steering stops), as they can have a tendency to become very united with the axle over time. Removal of the axle may be necessary, but if you're replacing springs, it has to come out anyway.  As for the kingpins themselves,...  As for the kingpins themselves, they usually slide right out with little effort. However, if they come out too easily, then you may be looking at replacing the spindles. Also, take note of the order in which everything comes apart so you're not scratching your head when it's time to reassemble.  With the spindles free from...  With the spindles free from the axle, carefully remove the old kingpin bushings from the outside in on both sides-never drive them the opposite way, as the bores are slightly tapered in towards the outside.  You may have noticed the axle...  You may have noticed the axle in the '53 was previously dropped (this one done by MorDrop years ago). The springs were also de-arched in an attempt to get the frontend as low as possible-but the results were questionable, so we'll replace the springs entirely. The axle turned out to be decent enough to retain.  With the leaf springs still...  With the leaf springs still attached to the framerails (and the truck securely supported), the axle can be removed. Take note whether or not wedge-shaped caster shims are being used between the axle and spring, as you'll want to reinstall them later.  Though LMC does offer replacement...  Though LMC does offer replacement springs, in order to retain the truck's lowered ride height, we were able to locate an appropriate used spring. However, LMC was the source for all the associated parts, such as shackles, bushings, pins, and all the hardware.  After the old springs had...  After the old springs had been removed, we noticed the rear hangers were very loose. To alleviate this, we removed the factory rivets and replaced with grade 8 hardware.  Next we replaced the frame...  Next we replaced the frame bushings and...  ...installed the new pins...  ...installed the new pins complete with shiny new grease fittings.  Then we did the same on the...  Then we did the same on the leaf springs...  ...before hanging them back...  ...before hanging them back under the framerails.  The springs will probably...  The springs will probably turn out to be the easiest portion of the job by far-just start by installing the new rear pins...  ...and then finish up the...  ...and then finish up the front by attaching the shackles to the spring eyes, and then finally onto the frame. That's it.  Now back to the spindles....  Now back to the spindles. The ones that came off the axle had definitely seen better days, and there was no question we needed a new set. Notice the damaged caused by an exploding bearing!  Fortunately, Bowtie Bits ended...  Fortunately, Bowtie Bits ended up having a good set in stock. Having ordered them while the springs were being installed, we hardly lost any time at all waiting for them to arrive.  As mentioned earlier, always...  As mentioned earlier, always work from the inside with the Oil-Lite bushings. A press is not required for installation; they should go right in, and usually without the aid of tools. Remember to line up the oiling holes in the bushings with the grease fitting holes on the spindles  It's also a good idea to do...  It's also a good idea to do a pre-run with the new king pins in your axle...just in case. With old dropped axles, it's not uncommon to find egg-shaped holes, but you also want to check excess play, which isn't a good thing.  Make sure and load the sealed...  Make sure and load the sealed kingpin bearing with grease before installing, and remember to put the rotating side against the axle, not the spindle. Make a test run without the kingpin to see how much play there is, which will help determine the amount of shims needed.  The spacer shims go on top...  The spacer shims go on top of the axle and beneath the spindle. With the kingpin installed, the shims should eliminate any slop between the spindle and the axle.  Before attempting to drive...  Before attempting to drive the stops in place (which go in from the front of the axle), make certain the machined slots in the kingpins are aligned appropriately-you may even need to rotate slightly in order to avoid getting the locks wedged in.  With an awl or small punch,...  With an awl or small punch, set the upper and lower grease caps securely in place. If the old ones were pinged in, you may need to carefully deburr the holes for the new ones to go in easier.  If your axle used the little...  If your axle used the little L-shaped steering stop tabs, don't forget to install those on the back of the lock pins as shown. Now the axle can be reinstalled under the truck.  With the rather heavy I-beam...  With the rather heavy I-beam supported on a tranny jack and lifted in place, a tie-down strap was used to help align the axle perches with the leaf spring pins.  Once the axle has been snugged...  Once the axle has been snugged tight with the U-bolts and the shocks reinstalled, the suspension is good to go. Now we can set our sights on rebuilding the brakes and installing the new steering components. | Sources | LMC Truck 800-562-8782 www.lmctruck.com | Bowtie Bits 316-941-9331 www.bowtiebits.com |
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