Towing w/Eldorado

[rbotti]

These days with every kind of truck on the market my question may sound strange but I don't have the room to buy a truck so here it is.

I remember back in the 1960's, my uncles who lived out in the country, used their Cadillacs to pull horse trailers and the like. Hey it was a Caddy they said, when you have one who needs anything else. Well that was 40 years ago, but in the near future I will need a way to transport my antique car to a few car shows. I’m wondering if a 90’s era Eldorado ESC could be used to pull a trailer with car, about 4,000 pounds. The engine certainly has the torque and horsepower, but I’ve never seen any of my old car buddies tow anything with a front wheel drive vehicle.

What do you do think?

Rick

Edited February 9, 2008 by 29Roadster

[Ed Hall]

The guru mentioned in the past about towing with the Northstar engine. He said that these cars tow well and can handle up to 6000 lbs. It should be able to handle the trailer with car fine. If you plan to tow, keep the transmission in 3rd gear to keep the transmission from hunting. Personally, I would also get a transmission temperature gauge and also put on the biggest transmission cooler I could find.

[JasonA]

No, no, no. The car is only rated to tow 1,000 pounds. Check your owner's manual. The engine and transmission may physically be up for it, but the chassis/frame and suspension and brakes were not designed for it. Old Cadillacs were huge body-on-frame cars (like trucks, just lower). If you need to tow, do it with the proper vehicle. Back then, Cadillacs were close enough to trucks to get the job done. Today, they're highly-refined sport sedans and coupes that are not designed with that tow weight in mind.

[BigCat83]

I own a '97 Eldorado, been under it many times.

The rear of that car is NOTHING but sheet metal; I don't where you could mount a hitch, if you can mount one at all.

I wouldn't.

[Ed Hall]

I'm going to post some articles the guru wrote. You make your own judgment call whether or not you want to tow with your Cadillac. The guru said that up to 3000 lbs is alright but over that, the transmission cooling becomes an issue. That's why I said install the biggest tranny cooler you can find. You can buy class 3 hitches for these cars. One caveat is you won't be able to use load distribution since these cars don't have a frame.

Another thing to consider is how much experience you have at towing. Someone who is experienced at towing has a good feel for the limit of their tow rig and they know how far to push things without getting into problems. As a result, they can pull much larger loads with inferior equipment than someone who hasn't had much experience.

Towing with 96 Eldorado

Generally, trailer towing capacity is based on the cooling capacity of the vehicle. Almost without exception "towing packages" consist primarily of extra cooling capacity for the engine, trans, engine oil, etc.

The frame intregral construction of a 96 is fine for towing lighter loads...up to 3000 pounds I would say. Over that and the vehicle is going to be sujected to more loads than it was designed for and the cooling will become a real issue.

If yours is a standard car then I would suggest several things for towing any sort of load. First, add more transmission cooling capability. An air to oil cooler in series with the radiator end tank cooler is advisable. You can't put too big of a trans auxilary cooler on as the trans takes most of the grief in towing. Second, add more oil cooler. Your car probably already has an oil cooler in the radiator end tank. Look at the oil filter mount and see if there are hoses exiting the oil filter adapter that bolts to the block. You should be able to see the hoses above the oil filter itself. If so , then you have the basic requirements for an oil cooler. splice the hoses near the radiator fittings and add an auxilary air to oil cooler for the engine oil. A 93 STS had an auxilary air-to-oil cooler that would work nicely and you will just have to fabricate lines for it to install it in series with the radiator cooler. There are bigger radiators for the car available...although you'll have to shop around. I don't think there were specific trailer towing rads for your specific car but by crossreferencing the radiators for other models a heavier duty rad may be available. I leave the rad last because you can monitor coolant temp while towing and back off or pull over and idle if it gets too hot. Hard to guage the oil and trans and do the same.

Otherwise, use common sense when towing. You will probably just want to put the shift lever in 3 and leave it there. Forget 4 or overdrive. It will lug the trans , create more heat and slippage and run hotter. It will also put much more load on the torque converter clutch (your car has a VCC that constantly creeps under load for smoothness...not the best arrangement for towing) The engine will live fine at the higher RPM's in 3 and will actually be quite happy at 65-70 MPH in 3 with a trailer. Watch the temps if you get into hills and grades...especially the long freeeway grades and low speed, steep grades in the mountains...that is where the engine coolant temp will shoot up.

Personally I have towed a LOT with the RWD Cadillacs and they make excellent tow cars as long as you maintain a bit of common sense, don't treat them like trucks and keep the trailers relatively small. I would hesitate to tow much over 3000 pounds period. Especially for a long distance. I routinely go non-stop 400 miles with 1500-2500 pound trailers and the cars do fine as long as properly epuipped.

Remember that in the winter, towing might seem easier (the engine coolant temp is rarely a problem) but the engine oil and especially the trans do not care if it is cold or hot outside....they can easily overheat even on freezing days and the trans can be totalled on a cold day when everything else is nice and cool. The load on the trans is there regardless of the ambient and extra cooling and care is required.

Towing with STS

Either of your STS's would make a fine tow car. FWD cars tow excellently. I use a FWD Cadillac for a tow car all the time and esecially during the winter with snowmobiles in ice and snow they are great. Far more stable on slippery surfaces towing as the rear end does not step out when the wheels spin which would really tend to upset a trailer.....but I digress. Search in the archives using "trailer towing" and there are some prior posts on the subject that go into detail. Use the forum search feature in the tool bar.

The hitch for the 94 is a no brainer. It is a simple install and clears everything. The hitch for the 98 is a bit more complicated as you have to cut a hole in the rear fascia to clear the receiver. It looks fine when done but unless you want to cut the hole and keep the hitch on the 94 would be the choice.

The 94 is a better pick anyway as the transmission has a torque converter clutch instead of a viscous converter clutch which is a little better for towing. You won't have any tongue load to worry about but you will pull some weight obviously pullling another car so run in 3 gear all the time to ease the load on the trans and keep the speeds down to sane levels. I wouldn't push it over 70 with the car behind you. It will run about 3500 all the time which is fine in 3 for towing.

Anyone who says the FWD Cadillacs cannot tow has obviously never tried it. They work fine. I wouldn't hesitate to tow a car on a dolly like you describe.

As with any car with electric fans engine cooling is the usually limitation. Trucks that can tow very heavy loads have engine driven fans for max cooling but cars with electric fans are limited in that way. Just make sure the cooling system is fresh and change the oil before and after the tow to make sure the oil (which will run hot even with the oil cooler) isn't degraded excessively.

Adding Hitch

You might consider an auxilary trans cooler if you are going a long distance like that. The trans takes the most abuse in towing due to the steady load on it. For a one shot deal like you describe I would suggest an aux trans cooler in series with the radiator end tank trans cooler and don't worry about the oil cooler. For the trip I would change the oil immediately prior to leaving and immediately upon arrival. The oil will get warmer than normal and possibly pretty hot going thru the mountains but it should live fine....it will just age it severely due to the heat and time. Change it at the other end and don't worry about it. The oil life monitor does an excellent job of predicting oil life and will take the added load of the trailer into account based on the higher engine load and RPM. Reset the oil life monitor when you change before you leave and watch it occasionally. If it decrements very quickly to zero oil life or recommends a change enroute due to heavy trailering load then I would hit a quickie oil change place enroute. If you are really concerned about the oil temp....have Mobil1 synthetic installed at the change before you leave (don't tell anyone I told you to use synthetic...LOL). The synthetic oil gives much better high temp operating characteristics and will easily take the higher temps with towing should you get into a heavy head wind situation or something where the oil is potentially overheated. It would just be cheap insurance for the trip with the trailer.

I would recommend keeping the speeds down and run the trans in 3 not overdrive for the trip. The engine will not mind the extra RPM at all and the trans and VCC will appreciate keeping the load off. If you run in 4 or overdrive the trans will be lugging all the time and seeing high slip rates across the VCC and the torque converter creating a lot of heat. Just put it in 3 and drive. I run for 400-500 miles steady in 3 all the time with STS's and they love it...don't worry that it is revving a little fast....the Northstar handles that fine. It will run forever at 3500-4000 RPM constant.

If you are pulling an upright trailer like a boxy U-Haul enclosed trailer or something keep in mind that the aero load is going to be much worse than the weight. Most people tend to fixate on the wieght of the trailer due to hitch limitations and such but once on the go that aero load can cause heavy loading on the engine/trans continously on the expressway. The trailer might seem light and easy to pull at low speeds but, even empty, the trailer can cause high aero loads. And look at the weight of a U-Haul trailer. Even empty, they can weight 1500 pounds!!! The trailer may weigh more than your stuff inside. The aero loads can be kept in check by keeping the speeds down and accounted for by always running in 3 to ease the steady pull on the trans which can heat it up more than a WOT blast up a hill at high RPM. Plus, if you put the lever in 4 or overdrive the trans will likely shift a LOT and hunt some between gears and/or applying and releasing the VCC. The hunting and shifting can really heat it up also. Just keep it in 3 to avoid the headachess. There is a protection algorithm in the PCM to keep from overheating the VCC in the torque converter so running in 4 with a decent size trailer for long distances is likely to trip that and turn on a message. There is also a trans temp sensor to protect it in the event it does get over heated. If you do get into a trans temp message even running in 3 then pull over and idle and allow the trans to cool off. It will cool off much quicker idling than turning it off.

The main thing is to use some common sense when towing. You can't just pop the cruise on at 80 and forget about the trailer. The steady extra load can really (will really) heat things up so keep an eye on things , run in 3 , keep the speeds down to 65-70 at most and it will tow fine.

Edited February 9, 2008 by Ed Hall

[WarrenJ]

Edited to delete stupidity.

[JasonA]

The frame intregral construction of a 96 is fine for towing lighter loads...up to 3000 pounds I would say.

Anyone who says the FWD Cadillacs cannot tow has obviously never tried it. They work fine. I wouldn't hesitate to tow a car on a dolly like you describe.

Up to 3000 pounds "I would say". That's not exactly a statement based in fact.

Of course we haven't tried it. There's a reason that Cadillac specifies the maximum towing capacity at 1,000 pounds. If you tow above that, especially FOUR TIMES that much, there are two key words: "liability" and "negligence". If you tow at 4x your vehicle's rating, and you get into an accident, guess what the first thing is the other person's attorney is going to do -- that's right...have your car and your trailer weighed. He will find that you're way over the specified weight limit, and it's a slam dunk case for him. Your insurance company may have a hard time covering you, after you knowingly towed a trailer way outside what Cadillac tells you in the owner's manual.

There are reasons why Escalades are rated to tow close to 10,000 pounds -- and there are reasons why FWD Cadillacs are rated to tow in the neighborhood of 1,000 pounds.

Someone who is experienced at towing has a good feel for the limit of their tow rig and they know how far to push things without getting into problems. As a result, they can pull much larger loads with inferior equipment than someone who hasn't had much experience.

I personally feel that's a very unfortunate statement to make. To me, that's the same as saying "an experienced driver could mount slicks and drive in the rain, and do it much better than someone who hasn't had much experience." While it may be true, there's not a good reason on earth to attempt to do so. The first time a kid rides out into the middle of the street on a bike and you can't stop because you're towing more than your vehicle's rating...you'll know why.

Rick, PLEASE don't tow a car with your Eldorado. There's a very good reason why you've not seen your car buddies do the same.

[rbotti]

Thank you everyone for the advice, it was just what I was looking for. I've decided not to tow my antique car with the Eldorado. With 4,000 pounds of trailer loaded with an car to pull, I would need a towing capacity in excess of my load, say a total of 5,000 pounds. I will look to other ways of getting my old car to our next meet in Oregon.

Thank you again,

Rick

[stefank]

In my German vehicle documents towing capacity is determined as 907 kgs for a trailer with brakes and 750 kgs for a trailer without brakes (see pic).

Compared to other cars of that size this is rather low, some rivals manage to tow more than two tons.

Stefan

[JasonA]

Stefan, thanks for that bit of info. It appears to be about 2,000 pounds for a trailer with brakes, and about 1,600 pounds for a trailer without brakes.

My 2001 STS's owner's manual lists the GCVW (Gross Combined Vehicle Weight) as 7,100 pounds for an SLS and 8,100 pounds for an STS. That means that ALL TOGETHER, TOTAL, your vehicle, occupants, fuel, cargo, trailer, etc, cannot weigh more than that amount. That tells you exactly how much your trailer can "legally" weigh. My STS probably weighs close to 4,100 pounds empty. With two occupants, some stuff, fuel, etc, and it's probably above 4,500 pounds. So the trailer could then weigh up to about 3,600 pounds.

But that's not all. The GVWR on the tire inflation decal lists the total weight your vehicle is intended to carry, and while this doesn't include the trailer weight, you DO have to add the tongue weight, since that is carried by the suspension. My 2001's GVWR is 4,995 pounds. That means that if my car weighs over 4,500 pounds with occupants and fuel, the trailer's tongue weight cannot be more than about 500 pounds.

Incidentally, it's not THAT hard to overload a car, even without a trailer. My 2001's GVWR only gives me about 900 pounds to load, and that includes people. Put four big guys in the car with golf clubs, and you're right there.

Examine your owner's manual and the GVWR listed on your tire inflation decal for more information, and to find out your particular car's EXACT tow limits. I agree that your total trailer weight is going to approach 5,000 pounds with a vehicle and the trailer and anything inside it. That's just too much for one of these cars. Towing snowmobiles or jet skis -- that's a totally different story. But towing other vehicles -- I'd leave that to a more capable vehicle. It's just not worth the risk.

[navion]

I don't want to get in the middle of this discussion, but there is a couple of points that I would like to make.

If you are thinking about towing any trailer carrying 1000 pounds or more with a car or small truck, do yourself and others a favor and tow a trailer that has brakes and that they work!

Ditto for the lights! It is dangerous and frustrating for other drivers to be behind a tailer that has no or partially working stoplights or turn signals. Trailers tend to have a high rate of bulb mortality due to the vibration that they experience.

Due to that fact, ALL trailer lights (and tow vehicle lights) should be checked for proper operation each and every time the trailer is hooked up to the tow vehicle!

Take Care

Britt

[Ed Hall]

Boy I sure opened a can of worms quoting what the guru (who was a GM engineer) said. Edited February 10, 2008 by Ed Hall

[KHE]

I tow a covered, two-place snowmobile trailer with my STS but that's about the limit that I'd tow before I'd change tow vehicles. There is a lot of wind resistance fron the cover that adds to the effective weight of the trailer. My Fleetwood Brougham is rated to tow 7000 lbs. but I store that car for the winter...

The STS has PLENTY of power to pass on a two lane road with the snowmobile trailer in tow.

[Bruce Holcomb]

On 2/9/2008 at 8:09 AM, BigCat83 said:

I own a '97 Eldorado, been under it many times.

The rear of that car is NOTHING but sheet metal; I don't where you could mount a hitch, if you can mount one at all.

I wouldn't.

I installed a hitch on my 02 Eldorado etc and the mounting holes were already there. I know cars unibody but if your not a idiot you can pull a 5,000 pound travel trailer if you towed alot. Ive never had a problem 

 

 

[Bruce Holcomb]

On 2/9/2008 at 8:01 PM, JasonA said:

Up to 3000 pounds "I would say". That's not exactly a statement based in fact.

Of course we haven't tried it. There's a reason that Cadillac specifies the maximum towing capacity at 1,000 pounds. If you tow above that, especially FOUR TIMES that much, there are two key words: "liability" and "negligence". If you tow at 4x your vehicle's rating, and you get into an accident, guess what the first thing is the other person's attorney is going to do -- that's right...have your car and your trailer weighed. He will find that you're way over the specified weight limit, and it's a slam dunk case for him. Your insurance company may have a hard time covering you, after you knowingly towed a trailer way outside what Cadillac tells you in the owner's manual.

There are reasons why Escalades are rated to tow close to 10,000 pounds -- and there are reasons why FWD Cadillacs are rated to tow in the neighborhood of 1,000 pounds.

 

I personally feel that's a very unfortunate statement to make. To me, that's the same as saying "an experienced driver could mount slicks and drive in the rain, and do it much better than someone who hasn't had much experience." While it may be true, there's not a good reason on earth to attempt to do so. The first time a kid rides out into the middle of the street on a bike and you can't stop because you're towing more than your vehicle's rating...you'll know why.

Rick, PLEASE don't tow a car with your Eldorado. There's a very good reason why you've not seen your car buddies do the same.

That's for to protect Cadillac from lawsuits. If you're not a idiot i pull my 5,000 lb travel trailer from ms to. Phoenix every  year. I go the southern route thru el Paso so not many hills. I drive 60 mph or so and  i keep tranny in 3rd gear. My car has 114,000 miles. The transmission holds a massive 17.5 quarts of oil that's almost 3 times more than most vehicles