1972 RevCon Front Suspension and Steering Rebuild PARTS LIST

[BJohnsonsv]

I have completed the front suspension and steering system rebuild on Flatnose Frank.

I started the project on Aug. 1, when a bearing replacement turned into the job I knew was coming. 3 weekends later, all parts are fit, secured and read to install wheels and get to the alignment shop.

Key takeaways:

• Every part is still available (with the exception of the bell crank, still a mystery), and generally reasonably priced. Rare Parts Inc. is a great company with better-than-new quality (and you pay for it).
• Be prepared. It was a physically challenging, heavy, and greasy driveway job that required many old-pro mechanical tricks and quality tools, including a press. Not suggested for the inexperienced. I knew what I was getting into..but SHEEESH.
• Suspension is ALL Oldsmobile Toronado / Cadillac Eldorado (as expected, but there was some talk online of RevCon-specific parts, maybe in later years)
• Steering box is from Chevy trucks.
• Powder coating the parts was well worth the cost. I don't expect to ever do this job again, so I wanted to ensure rust will never be an issue (at least for another 50 years)

I have shared a photo album of the process. Not every step, but it should give a good overview of the job. I was not able to find any of this online, so I hope it helps.

1972 RevCon front suspension and steering rebuild photos - Aug 2020

And most helpful, I suspect, A PARTS LIST of all the parts I used. I sourced them across 4 suppliers. Much of this list came from a couple other RevCon enthusiasts, but I had to do a lot of sleuthing and cross referencing to find them all.

1972 RevCon 250 D/T front suspension, steering and brakes PARTS (Google sheets)

Note: this is for my 1972 RevCon 250D/T. A second production year model. I know RevCon made changes, but many parts should be the same.

[otrt]

wow, beautiful work!

[Curtis in TX]

LIke rebuilding an IFS 4 Wheel Drive Truck, only BIGGER!
Impressive. Nice to see I'm not the only one smart/ dunb enough to do stuff like this.
But, I like to know my Rig work is done right. It's never been about the money. For me working on crazy stuff is a Hobby.

Some Men chase balls all over fields of grass, others spend their fortunes to play on the water.
We Gearheads enjoy getting things apart, and the challenge of putting it back together.
Usually in better shape than the way it came apart.

Well Done Sir!

[BJohnsonsv]

Originally Posted by BJohnsonsv

I have completed the front suspension and steering system rebuild on Flatnose Frank.

I started the project on Aug. 1, when a bearing replacement turned into the job I knew was coming. 3 weekends later, all parts are fit, secured and ready to install wheels and get to the alignment shop.

Update: Post professional alignment (I used a reputable fleet truck maintenance company), and after a thorough test drive over a small pass and on the freeway....

This is the single most impactful drivability improvement I've made to this vehicle .

It literally transformed the driving experience. It wasn't terrible, but now it literally drives like a Cadillac (it is Eldorado suspension after all). Smooth, quiet, predictable, straight, responsive. I easily hit a sustained 70mph with one hand on the wheel (on a 6 lane freeway). I never felt comfortable above 55 before. It was a LOT of work, but the reward of safety, comfort and confidence is amazing.

Oh, and the Wilwood brake upgrade with the D52 kit (plus 1.2" spacer and hub stud replacement) improved braking efficiency by at least 20-30%! The 1/2" outboard offset per side may just have improved stability a tad.

[Curtis in TX]

Fantastic results!
Love it when a plan comes together.

[BJohnsonsv]

Originally Posted by Curtis in TX

Fantastic results!
Love it when a plan comes together.

Oh yeah. You and me, both, @Curtis!

[Daveinet]

Just checking on the photos. Is that the stock lower A-frame? I was thinking the stock one had a strap welded around the outside of the lower ball joint to strengthen that area. In the famous brickyard test, the lower A-frame ball joint ripped out. My understanding is they strengthened that area by wrapping 1/4 x 1 inch wide strap around the end. I've only seen one flat nose and it had the strap.



Still wondering if anyone has found a rear disk brake conversion for a flat nose. I made the conversion for my slant nose, and the improvement was beyond incredible. I have a photo of when I broke the 100 mph hour barrier. It shows a pickup truck cutting in in front of me. I dropped a good 20+ mph in a very short distance with no brake fade.

[BJohnsonsv]

Originally Posted by Daveinet

Just checking on the photos. Is that the stock lower A-frame? I was thinking the stock one had a strap welded around the outside of the lower ball joint to strengthen that area. In the famous brickyard test...

Still wondering if anyone has found a rear disk brake conversion for a flat nose. I made the conversion for my slant nose, and the improvement was beyond incredible. I have a photo of when I broke the 100 mph hour barrier. It shows a pickup truck cutting in in front of me. I dropped a good 20+ mph in a very short distance with no brake fade.

@Daveinet:
1. Yes, these are the OE RevCon arms with the steel strap reinforcements (see pic.). I actually had to clearance one of them a very small amount because I couldn't get the OEM ball joint out. Do you have any articles or reference to that famous brickyard test? I've never heard of it, and would love to see it, as I suspect others would, too!
2. I would not want to see 100 mph in this vehicle anywhere but on a flat, closed track. But I will say that with the suspension rebuild, 70mph is smooth and quiet, so I can see how faster is feasible...but not on a public road.
3. I have begun research on a rear disc conversion. It it totally feasible, but I am convinced it won't be an off-the-shelf kit...but will use a kit that is easily modifiable, likely one of Wilwood's. I fully expect it will add yet another significant improvement to this rig.

The next 3 projects are:
1. Cooling system upgrade with aluminum radiator and twin cooling fans. This is happening next w/e. I have all the parts from Champion Cooling Systems in my garage.
2. Electronic Fuel Injection (EFI). Looking at Holly's Sniper kit since it's been successfully used by other RevCon owners (Neo RevConeers?).
3. The rear disc brake upgrade.

But, that list there ^ is easily another $5000 in parts . Will need to refill the car hobby coffer for a while, and just enjoy Flatnose Frank as is for a few thousand more miles.

[Daveinet]

I don't know if there is a formal article about it, but it has been mentioned over the years in various articles. Basically what happened is that when John Hall went to order 25 half frames for the first production run, GM wanted to know what he was up to. When GM found out, they required 5 chassis to be built up and weighted with sand bags to simulate the load of a fully built coach. GM then ran these on their test track. I don't know how many hours they were run, but it was several days of continuous running. The only thing that failed was the lower A-frame. It was repaired/beefed up and the test continued. Something interesting - that is one failure point on the GMC. Theirs are just stamped steel.

As for breaking the 100 mph barrier, I think the slant noses handle slightly better than the flat noses, as their front track is wider. There is also anti-dive integrated into the suspension geometry.

As far as the rear drum brakes, on mine, it was a kit specifically made for the 8K Dexter trailer axle. It was a direct bolt on kit, with no real modifications. For me, it was just having the courage to order the kit, hoping the spindle matched the spindle on my coach. As it turned out, it matched, so that made it a direct bolt on replacement.

The biggest issue with drum brakes is that they use the rotation of the drum to increase braking force. As a result, there is a delay before that force builds up. Not only that, but the resulting applied force is a little unpredictable. So under hard braking, it is difficult to apply the brakes without locking the wheels. Once the wheels lock, you loose braking. Even worse than the inherent delay, there is a distribution valve that does not allow the rear brakes to come on until the front brakes are under pressure. This exaggerates the delay, making panic stops much more panicky. I don't know how many times previously I would get into a situation where there was a light change, or someone would cut in front of me. I'd slam on the brakes and wonder if I was going to get stopped in time. Once switching to disks, those kinds of stops were not even panic stops - just a casual hard braking. When you think about it, if you have so much as a .5 second delay before full braking, at 60 mph, that is 44 feet! That is a lot of distance between you and whatever was making you stop.

[BJohnsonsv]

Originally Posted by Daveinet

I don't know if there is a formal article about it, but it has been mentioned over the years in various articles. Basically what happened is that when John Hall went to order 25 half frames for the first production run, GM wanted to know what he was up to. When GM found out, they required 5 chassis to be built up and weighted with sand bags to simulate the load of a fully built coach. GM then ran these on their test track. I don't know how many hours they were run, but it was several days of continuous running. The only thing that failed was the lower A-frame. It was repaired/beefed up and the test continued. Something interesting - that is one failure point on the GMC. Theirs are just stamped steel.

As for breaking the 100 mph barrier, I think the slant noses handle slightly better than the flat noses, as their front track is wider. There is also anti-dive integrated into the suspension geometry.

As far as the rear drum brakes, on mine, it was a kit specifically made for the 8K Dexter trailer axle. It was a direct bolt on kit, with no real modifications. For me, it was just having the courage to order the kit, hoping the spindle matched the spindle on my coach. As it turned out, it matched, so that made it a direct bolt on replacement.

The biggest issue with drum brakes is that they use the rotation of the drum to increase braking force. As a result, there is a delay before that force builds up. Not only that, but the resulting applied force is a little unpredictable. So under hard braking, it is difficult to apply the brakes without locking the wheels. Once the wheels lock, you loose braking. Even worse than the inherent delay, there is a distribution valve that does not allow the rear brakes to come on until the front brakes are under pressure. This exaggerates the delay, making panic stops much more panicky. I don't know how many times previously I would get into a situation where there was a light change, or someone would cut in front of me. I'd slam on the brakes and wonder if I was going to get stopped in time. Once switching to disks, those kinds of stops were not even panic stops - just a casual hard braking. When you think about it, if you have so much as a .5 second delay before full braking, at 60 mph, that is 44 feet! That is a lot of distance between you and whatever was making you stop.

@Davinet

Well there you go, you just documented an amazing story! And, you identified a very tangible area where RevCons are better built. It's ironic that the GMC's don't have the same reinforcement (and thus, they have an arguably dangerous weakness). It seems to fuel the stories I've heard that GM let John Hall prove the concept for the GMC motorhome before building his competition. Seems they even made it tough on RevCon by holding them to higher standards than they did for their own vehicles!

Regarding the disc brake conversion you used, I'll certainly look into the Dexter kits. They look like a good option, too.

[Daveinet]

The kit I used was made by Kodiac for the Dexter axle. Dexter also makes their own conversion, but it is way more expensive. They also do not have the option for stainless calipers and pistons. I chose stainless before stainless does not conduct heat very well. This makes it less likely to boil the fluid. That may have something to do with why I could brake so hard at 100 mph with no fade. The guy I sold it to towed a minivan through the Smokies with no brakes on the minivan or dolly. He stated he had no issues with brakes on in any of the mountains. My coach was a tandem axle. Fully loaded, the coach only had 8500 lbs shared between two axles. The brakes are rated for 8000 lbs per axle, so I had 16,000 lbs worth of brakes carrying 8500 lbs, so I was way oversized. That may have helped.

You know its funny, when I had it up 4sale I took a guy for a ride who had rebuilt 3 GMCs. He was amazed at the handling and of course the braking. He stated you can tell anyone this coach handles way better than a GMC.

[Curtis in TX]

Dang it guys! Now you got me thinking of swapping out the drum brakes on my tag axle to disc. Already have disc brakes on the front and drive axles. Big ones too!

I rebuilt them about 10 years ago, when i out limited slip in the differential, and thought it odd the tag was just drums. But now that you've mentioned Dexter disc brake conversions I'm thinking why not? It's only my kids inheritance money after all. They don't need it......

AND
I like to stop!

Oh and I've been known to run 95 in my Fleetwood across West Texas. Wife hates it when I go that fast. Says it makes washing dishes in the sink kinda iffy. (True story)

Now with double the HP I can't wait to get on a straight desert highway.

[BJohnsonsv]

All it takes is (more) time and (more) money

[Curtis in TX]

Originally Posted by BJohnsonsv

All it takes is (more) time and (more) money

Yep!

Got it figured out and am now waiting on parts. The Disc Brake Conversion should cost me around $500 - $600 ish. Still talking to my Fabrication Shop about making me a bolt on brackets to mount the disc brakes with. Need the brake calipers and rotors to design the brackets. There are some commercial brackets that can be bought, but no gaurantee that they will fit my bolt pattern on the axles end. (You can see the bolt pattern in the above picture.)
So I'm just going to design one I know will work, and have him water jet cut them for me.
This shop and I have done business before so I trust him.

I owned a Custom ADV Motorcycle Fabrication Shop for 16 years.(No Not Harleys)
So he has done a lot of crazy stuff for me before.

I'll link up the build in the Fleetwood Section once I get it going better.