Quote:
Originally Posted by CamperMX
I'm in the process of rebuilding a 1959 Avion Rover, 23 ft, single axle. I'm going to replace the entire axle assy and would like to get more ground clearance. The current axle is a 4" drop.
My question is this: Is it a good idea to install a straight axel, which would give me 4" of lift. Ride/towing issues? Experienced opinions are appreciated.
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Welcome to the world of Avions!
We have had the next year & next size down Avion from yours since 2011, & yours later morphed into the Avion H24 Holiday in 1960> MY with added length & a reworked galley & cabinetry, then later lengthened another foot to 25' H25 in about 1966-67 MY. You'll see the difference in period photos of the R23 vs H24/H25 in document links at the Silver Avion link at the bottom.
You didn't say whether your Rambler was single or the optional dual axle., but a dual axle one will double your costs, vs. to reaxle a single axle Avion.
In the
1960 MY Avion had upsized their line-up by a foot & updated their galleys & bathrooms (core parts are the same on all sizes of Avions during the Cayo ownership), in order to keep ahead of competition, & the 1959 S19 Sportsman was upgraded from a 2 sleeper (dinette/bed or Gaucho sofa-bed up front), into our 4+ sleeper
1960 Avion T20 Tourist with an added foot of body length, a reworked galley that replaced curbside cabinets with an amidships Gaucho sofa/bed plus a dinette/bed to sleep 4 + an optional 5th rollout bunk that could be added above the amidships Gaucho sofa/bed for the 4+ sleeping.
I think that your longer 1959 23' is only about a couple of 100 pounds heavier empty weight than our 1960 20' (actually 21'-6" OA) is going to be a very close comparable for this question.
Remember that our Avions were built different & sturdier than even the vintage Airstreams, including that our axles were much heavier duty than were used on the Airstreams of the day, with solid steel cast axles (with a sort of figure 8 or top & bottom lobes reinforced cross section) & leaf springs - rather than the AS hollow tube torsion bar axles.
They were lowered with a 4" drop axle for better towing with autos of the day, which was actually a truck based axle & leaf springs for heavy duty service & safety, as were the OE 15" split-rim 6-Lug truck wheels (but do change the wheels to solid rims, since they're dangerous to change split-rims - there are a couple of vintage trailer tire & wheel suppliers near you in OH & IN & even Coker in TN).
So you may not get the same ride quality nor sturdiness from some other "modern" torsion bar or other coil sprung etc. straight axle.
The original Avion axles & HD leaf springs can be easily & reliably refurbished or rebuilt with new leafs if they're sagging a bit - if they need anything - which worn out leafs may be the cause of any lower height droop that you may be experiencing. A far more cost effective media-blasting, re-prime & repaint may be all you need to do - & that's still cheaper even if a full leaf springs disassembly, restoration & rebuild if needed.
Having a year newer single axle
1960 Avion T20 Tourist (21'-6" L bumper to coupler - we have no problems with clearance on driveways etc. - except when I mounted a trailer rated bike rack in a 4" square bumper mounted 2" receiver that was flat on top of the bumper (the prior owners had replaced the original stock "C-section" Avion bumper, with a typical 4" square tube bumper to carry a modern 4" sewer hose when they were restoring it).
My solution was to buy an 8" L section of plain 2" square steel tube & another 2" receiver from eTrailer, which I had welded on top of the original 2" receiver of the bolt-on 4" RV Bumper hitch receiver (all were from eTrailer, but are widely available) - with the 8" plain tube cut into 2x 4" sections used vertically, between the original lower 2" receiver & the newly added upper 2" receiver.
You'll see at eTrailer & other towing suppliers some similar dual receivers with a straight plus an upper raised 2" receiver that plugs into a another 2" receiver on the TV, allowing for mounting a bike or gear rack above the trailer hitch on a tow vehicle.
That gave me the idea, but I didn't want to further extend the bike rack out from the trailer, nor add that much weight - so I improvised my standard 4" bumper mounted 2" hitch to have 2 hitch height options - but not to carry double items. You don't want that much weight nor added moment arm on your Avion's rear bumper - even if it has a sturdier 3 boxed-rail frame (Airstreams use only 2 lighter "C" frame rails).
Thereby, I gained 4" lift at the rear of our Avion for the bike rack for a fraction of the cost that you're proposing for a full axle replacement.
You don't say what underbody clearance problem that you're trying to resolve, so as others have said - if you don't need clearance for offroading, steep ramp to your property or something else requiring the added height.
If you need to raise it for that reason, then you may need to go to a local hot rod shop to get them to recast a similar straight axle & use the HD leaf springs sets L & R to match the HD carrying capacity of your OE axle/Springs.
They can probably also refurbish your existing axle/springs if you stay with the OE 4" drop axle, or refer you to the machine shop that they use.
The main downsides to the higher ride straight axle option are:
1. that it will look goofy with too much wheel well showing, & looking "jacked up" with a straight axle giving it a 4" higher body level;
2. you'll make it harder getting into & out of the Avion's steps at another 4" up, plus harder to do any roof, AC, vent, awning, etc. maintenance up higher;
3. it will change the drop or rise of your hitch bar or "stinger" (used for Hensley & ProPride 3P WD/AS hitches) with the trailer up 4" relative to your TV's receiver height (which may go beyond available 8" drop/rise tow bars & stingers), & that may also change the geometries of how the Avion & TV work together - possibly making it not tow as well (they're designed to tow smoothly with the 4" drop axle & lower trailer height & work well with either auto based SUVs & pick-ups);
4. it could change your trailer's weight balance fore & aft being up higher, & possibly change your WD hitch set-up & how you pack/load your Avion for good weight balance & tongue weight;
5. it will change the aerodynamics of your Avion behind your chosen TV, which will increase your towing MPG, & may induce or change the wind buffeting of the Avion in the TV's slipstream;
6. your costs to reaxle will be much more than to renovate, restore, clean-up & repaint, etc. your existing OE axles & springs - & that higher cost will double if your Rambler is a dual axle option model;
7. being 4" taller with its center of gravity up that much more above the road, you may find it will be more tippy & more susceptible to cross winds & uneven road pavement conditions, than originally designed;
... & perhaps other changes if you go with a straight axle.
If you look at the Avion ads of the day - as well as Airstreams & pretty much all "silver twinky" & "canned ham" travel trailer as of the day - they're all shown towed by low passenger cars & wagons - so they were likewise set up with 4" drop axles to keep them lower, well balanced & aerodynamic for easier towing.
Why change what has worked for 66 years?
Since Airstreamers' experience on here will be different, than with our Avions & Silver Streaks, Streamliners, & other competing silver twinkies of that era - you may also want to get involved with Avion specific forums & resources, such as the 2 below:
https://groups.io/g/AvionForum
http://www.silveravion.com/home.html
Hope this helps!
Good Luck!
Tom
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