You’ve heard the term, but perhaps you’re not sure what it really means. Here we show you what’s involved in turning stock spindles into flipped spindles
‘Flipped’ dropped spindles on the front of a Split Bus (or a link pin beam-equipped Bay) allow you to drop the ride height around 3.5 inches, and also narrow the track 9mm per side. The best thing about them, though, is the ride quality remains the same as stock. As a result, they have become a staple component when lowering a Split and, when paired with a narrowed, adjustable beam, allow you to go really low, too.
Whilst it is possible to buy some flipped spindles, this guide aims to show you how to save a lump of money by building your own. However, be aware, doing so does require the use of some specialist tools so, if you can’t yet fathom out an oil change, it may be best to buy a set. Whether you choose to make some or not, this will show you what’s involved in their construction.
- Parts needed: 2 x Split Bus spindles
- Tools used: 9, 13, 15 and 17mm spanners; Hydraulic press; Angle grinder with wire wheel, grinding and flap discs; Tapered reamer; Die grinder; Welder
- Skill level: 5/5 Hard
- Time taken: 12 hours
- Cost DIY: £50-£70
- Cost Pro: approx. £350
Split Screen flipped spindles: Step 1
Remove and strip spindles
Before we dive into the job, you should read the whole guide and amass the tools you will need to do the job. Although it is possible to press in and ream your own king pin bushes and ream the track rod reverse taper yourself, we chose to have a machine shop do the bushes as it is a laborious task. We had the necessary tools in stock to do it, but were lacking the time. If you have to buy the correct tapered and adjustable reamers, it makes this job much more expensive, so again it may be better to pay a machine shop to do this part of the job for you. Press tooling is another thing. We made our own out of scrap steel, but again, a good engineer should be able to press the spindles in and out for you if you are struggling.
Okay, all set? Cool. Then let us begin. Jack up and secure the Bus on stands and remove the front spindles complete. With the worst of the crud cleaned off and the spindles on the bench, take the 13mm and 17mm spanner and remove the steering stop bolt from the king pin. With this done, you can put the spindle in the press tool and push the king pins apart. Alternatively, take your spindles to a reputable machine shop, or a good motor engineer, who can do this for you.
Split Screen flipped spindles: Step 2
Dismantle and degrease
With the upper king pin pressed out, you can strip the spindle to its component parts. Tap out the spacer collar and you can then pull out the lower king pin. Discard all the grease seals, which will be well past their best, but carefully remove the fibre thrust washers from each king pin and put them somewhere safe for now. If your spindles still have them in place, knock out the lower grease caps with a socket extension, or similar, and put them to one side with the fibre washers. Now remove the large grease fitting with a 15mm spanner and the three smaller ones with a 9mm spanner and store them, too.
Now it’s time to clean things up. I prefer thinners for degreasing and a paint brush. You don’t have to go too mad at this stage, especially if they are going to a machine shop, but clean off any caked-on grease so you can get an idea of the condition of the king pins themselves.
Split Screen flipped spindles: Step 3
Fit new bushes
The first thing to do once your spindles are degreased and have dried off is to wrap the bearing carrier surfaces well with masking tape, as they are easily damaged. Put it on thick, you can cut it off with a blade at the end of the job.
Our new phosphor bronze bushes were supplied by AH Schofield (tel. 01457 854267) and were given to the machine shop with the spindles. If you look ahead to the pictures later in this article, you will realise the king pins are re-mounted upside down in the carrier, so be sure to give specific instructions when you drop off the parts. If there is any minor damage to the pins themselves, you have a couple of options: the first is to purchase new pins, the second is to ask the machine shop to clean the bearing surfaces up for you. My local machine shop does this on a crankshaft grinding machine, as they are hardened steel, so a lathe just won’t cut it. Literally.
If you want to fit and ream your own bushes, you will need to buy, or have access to, a 21-24.5mm adjustable reamer, and a lot of patience.
Due to the change in the configuration of the spindle when ‘flipped’, the steering arms sits closer to the chassis, which means you have to ‘flip’ the track rod ends ie insert them from underneath rather than on top (note you also need to run ’68 and later outer track rod ends). Again, depending on your mechanical competence, you may find it easier to get the machine shop to cut the reverse tapers in the steering arms for you.
Split Screen flipped spindles: Step 4
So, you have your spindles back from the machine shop with sparkly pins and new bushes fitted and reamed to size. Do a quick visual check to ensure the bushes were drilled at the grease points, otherwise you will not be able to grease them when installed!
Now it is time to modify the spindle bodies. As you have now mounted the king pins upside down, you will need to fit the link pins the other way round to original, or the camber will be way out. Basically, you will be running the pins in a back-to-front configuration. If you insert the upper king pin (originally lower) into the upper bush, you will see that a fair amount of metal needs to be removed for the pin to turn through 360 degrees.
To achieve this, you will need to mount the spindle securely in a vice, using soft jaw inserts so as to not damage the bearing surface. Take a 4.5-inch angle grinder with a metal grinding disc fitted and put on eye, ear and lung protection to be safe. You will also need to wear some sturdy gloves. Once you are set, carefully grind away material in the area shown above, stopping regularly to check the fit of the king pin. You are aiming to remove as little metal as possible to allow the king pin to work in its new location. We find it beneficial to ‘dish’ the area slightly, so it retains its strength at the edges. Once the pin turns all the way round, swap to a 40-grit flap disc and go over the area, polishing it so it looks ‘factory’. A top tip here is to fit the link pin into the king pin at this stage and check the rotation. Some aftermarket pins are pretty ‘fat’ in this area and need to be clearanced with a flap disc. Either this, or remove a little more material from the spindle itself.
Split Screen flipped spindles: Step 5
Okay, so now you have clearanced the spindle to fit the king pin, but there are a couple of other areas still to attend to. Not all dropped spindle builders do this, but over the years I have found going a little bit further makes the spindle fit and work better, so I will talk you through why we are doing them. Look at the picture here and you will see the spindle with three distinct areas ground down. The first is the one you attended to in step 4. The second area is on the bottom of the spindle, where it can come into contact with the lower link pin, potentially causing the steering to jam or have a tight spot. The third area is as a result of the lower pinch bolt in the trailing arm being very close to the steering arm when the spindle is re-fitted. If the steering arm catches on the pinch bolt at any point in operation, it will lock the steering which, needless to say, is very dangerous. Some people choose to grind the pinch bolt head down, but I prefer to remove a little metal from the underside of the steering arm (indicated by my finger in the picture above) in this area to aid clearance.
Running the king pins in this configuration means the pins are 4mm further apart than they were originally. Some people have the lower bearing face machined to correct this, but this makes the lower pinch bolt clearance even worse. As you will see, I do it a different way.
Split Screen flipped spindles: Step 6
Grind king pins
With the spindle body modifications finished, attention can move to the king pins. As you are now running the pins back to front, the side of the king pins that fit up to the torsion arm needs to be flat, otherwise you won’t be able to run the grease seals. “Just don’t run the seals” tends to be the advice given here, but this will greatly accelerate wear and, besides, it is very easy to get the seals to fit, with just a little more work here. In the picture above, my finger is pointing to the ‘notch’ on the king pins I am referring to, while the ones to the right of it have been modified. To do this, clamp the king pin securely in a vice and use a flap disc on the angle grinder to gently grind this area off, making it flat on both upper and lower pins.
Split Screen flipped spindles: Step 7
Ream out track rod end holes
As explained earlier, you will need to use 1968 onwards track rod ends, which will be run upside down ie inserted into the steering arms from below. If you had the machine shop do this procedure for you earlier, you can skip this step.
If you don’t have the correct tapered reamer, and do not wish to purchase one, you can buy ready tapered bushes, so all you have to do is drill an oversize hole and press the new bushes in. Butty’s Bits sell these, as do Retrodubs, amongst others.
Personally, I prefer to ream the holes, so mount the spindle in the vice and go slow with the tapered reamer (above), stopping regularly to check the fit of the later track rod end.
Split Screen flipped spindles: Step 8
Clean and degrease
That’s the end of the modifying parts section, so you can now clean the spindles in preparation for paint. If yours have a lot of rust and paint build up, you can either blast them, or use a wire wheel on a grinder to take them back to nice clean metal.
With this done, clean everything with a degreasing solution. You are aiming to clean not only the outer surfaces, but all the inner ones too, and inside all the grease fitting holes. It is very important there is no swarf left anywhere that could accelerate wear, or worse, so run a tap through all the bolt holes and the grease fittings, and clean carefully to make sure everything goes together easily.
Split Screen flipped spindles: Step 9
Prime and paint spindles
With everything cleaned and dried, it is time to put some paint on the spindles. You don’t have to do this stage, but it makes assembly more pleasant and keeps your Bus looking nice and tidy underneath. You can mask off any bearing surfaces or do as I do and hold them in a gloved hand to paint them, then clean off the excess on the bearing surfaces with thinners once dry.
Aim to get at least a couple of light coats of suitable primer and a couple more of a decent chassis black on the spindles, allowing the paint to dry thoroughly between coats.
Split Screen flipped spindles: Step 10
A word here on king pin seals. There have been a lot of problems with the original-style seals currently available for some time. They tend to split and fall off after a few months, meaning pressing apart the spindle again to rectify. This has been well documented on various VW forums. Consequently, I have been using nitrile o-rings for years now with no problems. To find the correct size, either take your spindle and kingpins, complete with thrust washers, to an o-ring supplier and ask them to find the perfect size, or give Martin at Ginger’s VW (www.gingersvw.co.uk) a call as he keeps the correct size in stock. You will need eight in total.
To re-assemble, insert the greased fibre thrust washers onto the king pins, then fit an o-ring to each one. Having greased the pins and bushes, fit everything together, so the spindle looks like the picture above to the right. Don’t forget the two o-rings on the spacer either, which can take a bit of jiggery-pokery to get in place. With this done, insert the lower pin into the upper pin, ready to be pressed into place.
To press the pins back together, you will need a hydraulic press. You can build a fixture to keep the pins in line when pressing, but I find a couple of old driveshafts turned down to fit into the link pin bushes works a treat. I then just eyeball it as the pins are pressed together. Don’t lean on the press too hard, as you may make the spindles unnecessarily tight.
Split Screen flipped spindles: Step 11
With the spindles pressed back together, there are a couple of final tasks to attend to. If you remember, I mentioned earlier on that there will now be a 4mm difference in the pin spacing. This means to get the M8 bolt into the upper pin you will need to grind the pin a little. A rotary burr on a die grinder works best for this. Keep checking the bolt as you go, as a snug fit is optimal.
Remember the grease caps you knocked out earlier and set aside? Dig them out, clean them up and flatten them if needed. As the upper kingpin now has an open bearing surface, it is advisable to tack weld a grease cap to the top of the spindle to stop ingress of dirt and premature wear. If your original grease caps were missing, you will have to make something. With the caps tacked in position, you can carefully touch up the paint.
Remember to check the offset of the trailing arms and shim the link pins to factory specs when re-fitting the spindles to the Bus. John Muir’s book, How To Keep Your Volkswagen Alive has the best explanation of this.
Words: Mark Walker