new member but not new to the world of modifying cars.

My daily driver is a 2005 2.4 LE. I bought it new and now has ~210,000 miles. I use my camry to pull a small 4x6 trailer on occasion for various things. I also converted the car to run on propane a few years ago. As such there is a few hundred extra pounds in the trunk. The propane tank is a 35 gallon tank (hold 28 gallons of propane). Empty tank weighs about 110# plus 28 gallons propane (~120#) plus the weight of the steel support that I had to put in the floor of the trunk to span the spare tire hole (maybe 50-75#) less the removal of the spare tire plus the weight of a donut spare. In addition there is the weight or the hitch. All in i would guess i am 300-350 pounds heavy in the trunk at all times. I would guess that I have pulled a little trailer for more than 20,000 miles over the years and is extremely useful. I live out in the sticks and I have a long trip to town so if i dont need to drive one of my trucks I opt for the camry and small trailer. I have a 1/2 ton dodge (10 MPG) and 1.5 ton ford (6 MPG) for the heavy stuff. I have pulled motorcycles, farm supplies, small equipment, boats, canoes, appliances, all kinds of stuff behind the camry.

It is time/past time to replace the struts and I was wanting something heavier for the rear to counteract the extra weight. I don't see any options out there.

 

You might not find what you want in a typically aftermarket strut assy but new OEM springs might pick up any sag due to age.

There are coil overs struts that allow height adjustment via an adjustable threaded ring. Most are set to lower the suspension about an inch, if interested call the manufacturer to find out if they can be adjusted to raise it instead.

Not sure if off the shelf heavy duty strut springs are available.

Toyota Racing Division (TRD) may have some kind of heavy duty spring but these tend to be designed to lower the car. As most custom springs do.

Vendors offer air suspension systems.

Or look for spacers for the strut assy spring. Called coil spring spacers or boosters. There are two kinds. One is a plastic donut design that adds space between the spring end and strut assy. This increases spring force. If you can't find one listed for your car, try to matching spring diameters with available products.

Don't confuse these with something called the insulator. This is a thin plastic shim that all struts use to prevent metal to metal contact between spring end and strut parts.

The other type is plastic clips that insert between the coils of the springs. This prevents the spring from compressing.

The coil springs can also be stretched, changing the spring rate. You need to find a shop for this but it is common enough. How much of stretch is needed, don't know. Would assume a competent shop could make an educated guess.

There are also businesses that only make custom coil springs for street rods, limo's and anything else you can think of. Don't know what a pair of custom springs might cost.

My own two cents is try to find donut spacers. If no luck try the spring coil clips. Look for heavy duty springs or have a new pair of quality springs stretched.

Might also contact any propane or LNG car clubs and associations for advice. Your not the first to add a tank to the trunk. Years ago Toyota offered a LNG powered Camry but this was not in the US.

As to the propane conversion. What was the reason behind this? Do you have access to a large mother tank? Did you install the conversion yourself, cost, MPG, benefits, problems, etc.

At one time considered a LNG conversion but the conversion, fueling station and NG costs were too high.

 

Thanks for the detailed input. I was planning to replace the strut assemblies fairly soon but was hoping for stiffer spring for the extra weight.

LPG was a no brainier for me. I have a 3,000 gallon tank at my house that I fill up on. I get massive volume discounts since I buy an entire delivery truck at a time. Since my conversion a couple years ago my typical GGE cost has been $.89 to $1.60. Prices are really low at this 10 seconds due to crashing oil prices. The traded wholesale price is hovering about $0.50 per gallon. I did the conversion myself and my before state tax credit cost was about $1,200. LPG is stored in liquid form and the range on the tank is huge compared to CNG (not LNG). There are a few CNG stations in my area but pretty sparse. CNG home fill pumps are expensive and slow. My actual cost has been much less than buying CNG at the public stations would have been. I get over 500 mile range on my LPG tank and the car still runs on gasoline as well.

I drive about 3,000 miles a month so the cost savings was substantial. My historical fuel savings has been in the $3,000 range per year. This year less due to lower gasoline costs. My kit has recouped more than 10X in the past couple of years.

No down side. Car runs as good as it does on gasoline. I even pull a trailer while running on LPG but I do have limits. The tune that I have programmed is good for about 500# trailer and anything more than that I either re-tune the computer or simply run on gasoline.

Big benefit other than cost and it is clean burning fuel. I change my oil at 20,000 mile intervals and it is still as clean as it was out of the bottle. I periodically sample my oil and send it in for analysis at Caterpillar and everything has always checked out.

I have converted my lawnmowers, generators, farm equipment, and general motors to LPG. Never have to deal with a gummed up carburetor or bad fuel again. I have kits to convert my other vehicles but lack the time to actually do the conversions.

 

Of course CNG.

Do you have a LPG pump or do you use a dip tube on the tank?

I own a 500 LPG tank for a pool heater. Had thought about running a smaller gas generator thus not needing to store fuel plus refilling 5 gal tanks for the BBQ, but got into issues of installation.

 

No pump. I used a dip tube when I started out filing from 500 gallon tanks. Now the 3000 gallon tank has the output at the bottom of the tank. The 3000 gallon one is 30 feet long on I beam skids. I would like to get a 5000+ gallon tank or tanks. Bigger volume the bigger the discount. Also allows my to only buy when prices are low.

 

Did your 500 gal tank come with a dip tube and/or hardware to tap off liquid?

Some issues with some dealers here about dip tubes/removing fuel even if tank is user owned.

 

When I first started, one of the local dealer gave me 1 year free lease on 2 500 gallon tanks with the dip tube. i was a high volume customer but the next year the lease on the tanks came up ($60 ea tank / year) and I decided to shop around again. I found a different dealer that waived the rent on the 3,000 gallon tank plus gave me a better deal. What I was surprised to find out when I started to price shop is that there was one company that bought up nearly all the local dealers so there is in fact very little competition. In the phone book there is about 10 "dealers" that deliver to my area but 8 of them are owned by the same company.

In addition to these tanks that are supplied by the dealer, I purchased a dip tube valve assembly off of ebay that can be added to a 500 gallon tank. This should only be attempted by someone that knows what they are doing.

 

Consolidation also happened in this region plus a good number of new tank farms have been installed.

I have refilling forklift and 20 lb tanks using a dip tube. Thus now having a tank thought about doing the same plus perhaps running a small generator. It is a source of energy that can be tapped for many uses.

The tank has a liquid withdrawal valve but not sure this is connected to a dip tube. If the tank were ever moved it would need to be emptied but not sure if the LPG is pumped out or bleed off via tank pressure.

Did you install the dip tube yourself?

I appreciate the caution about knowing what I am doing. I do my research on a project and determine if the job is within my skill range. If not I find someone who has the skills.

 

I did not install the valve. I believe that most or all tanks have the dip tube installed and it is the valve on the top that you need. The LPG companies need a way to withdraw the liquid from the tank in emergency. Sounds like you are already setup if you have the liquid valve. You just need a transfer hose which can be purchased for $100-$150. You propane company would probably sell you one. Just tell them that you bought a propane tractor. I fill up my BBQ tanks that I use for gas tanks for my lawnmowers and I have about a dozen forklift tanks that I use for various equipment and portable heaters.

If you ever take a valve off of a propane tank, it is dangerous. After you "empty" the tank, there is still propane in the tank in vapor form. Propane is heavier then air so it will settle in the tank. When you remove the valve, you will introduce the oxygen that can then get really dangerous. basically LPG has a molecular weight of 42 while O2 has a weight of only 32. Therefore propane sinks to the bottom. C02 is slightly heavier than C3H8 and would dissipate the propane from the bottle. So after flushing the tank with CO2 (i have a tank of c02 for my keggerator), you would be safe to install or replace valves. After installing new valves, you would need to use a vacuum pump to pump the tank down to get all O2 out of the tank before filling the tank (i use my HVAC vac pump). If you get 02 in the tank with C3H8 in the correct mixture with a spark you will end up on the 5 o'clock news. Also there is a special teflon tape or paste that should be used. I bought some of the paste but I had bad luck with it sealing. I found that the yellow tape has worked well for me. I have replaced dozens of valves for forklift and auto tanks.

 

Thanks for the precautions and great detail as to what is needed to be safe. I have an industrial vac pump and can borrow a CO2 tank. I will think about the process plus inquiry at a LPG dealer who might do the job if required.

The tank I have was new as of 2007 and appears to have the correct liquid withdraw fitting, see link:

https://www.dultmeier.com/products/0.763.772.3325/6708

Perhaps the tube is already installed.

I have seen propane dealers flame propane tanks from a distance, perhaps you know something about this. A tube having a something looking like a can at the end was connected to the top of the tank and flaming at the can. I assume they were trying to burn off gas before reconditioning the tank but don't know. Also assume there was some kind of flame arrestor or check valve installed to prevent a back fire.

Speaking of the 5 o’clock news I was in the local area a few miles away when the Atlas Foundry exploded in WA State. Their very large LPG tanks were being refilled when it appears a filling hose fitting had problems, the result being a large vapor cloud formed. This reached an ign source and an explosion happened. The filling process was caught on video. The truck driver didn’t stand a chance and died of burns. Truck parts ended up being thrown around closing the nearby freeway. Quite the show.