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Discussion Starter #1
Why is it that a Fleetwood with towing option is rated at 7000 lbs, and the Roadmaster with the towing option is rated only at 5000 lbs? The Fleetwood is around 300 lbs heavier to begin with.

What components allow for a higher rating on the Fleetwood? Is it because the rear-end and the transmission are more stout on a Fleetwood?
 

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Probably due to the higher numerically ratio gears available for the Fleetwood. On trucks the towing capacity is diectly related to gears. For example: 3.42 5000lbs, 3.73 7000lbs, 4.10 10,000lbs.
 

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Discussion Starter #4
Very good!

My 94 Roadmaster has a 2:56 posi and my 94 FWB has the 2:93 gears. I am not doing any towing on either, but was curious about the different specs.
 

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"9C1 Caprices with LT1s had 3.08, a 4L60E built to a 'pursuit' spec, and unique shift tables and line pressures accounting for both MpGs at low throttle angles and the likelihood of pursuits.
I suspect their ratings were 17 City, 25 HiWay, and 3000lbs[, but I can't be sure]."

I am pretty sure it is 5000 for LT-1 9C1's and the owner's manual says to tow in D.
 

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What I do is wire a switch on the electric fan cars so I can turn on BEFORE the motor gets hot such as a backup in the summer or getting ready to pull a hill.
When does the stock fan come on? Like 220 deg?

Why roast the motor then cool it down? With the mechanical fan it just stays cool.
 

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Gm advertised the Fleetwood as being able to tow that and do it in overdrive.
 

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What I do is wire a switch on the electric fan cars so I can turn on BEFORE the motor gets hot such as a backup in the summer or getting ready to pull a hill.
When does the stock fan come on? Like 220 deg?

Why roast the motor then cool it down? With the mechanical fan it just stays cool.
Most of us have the good sense to have a 160 Thermostat and a PCM tune with lowered fan turn on temps and adjusted shift points and increased pressure for crisper shifts as well as an aux trans cooler(9c1). If you don't at least have the trans tuned, you should install a Transgo HD2 kit. There is a Sonnax kit also I think. I wouldn't start towing with the stock setup anyway. The trans is the weak link in all of this.
 

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Why is it that a Fleetwood with towing option is rated at 7000lbs, and the Roadmaster with the towing option is rated only at 5000lbs? The Fleetwood is around 300 lbs heavier to begin with.

What components allow for a higher rating on the Fleetwood? Is it because the rear-end and the transmission are more stout on a Fleetwood?
V4P Fleetwoods had 3.42, a 4L60E built to a 'towing' spec, and shift tables and line pressures written specifically for towing, to the detriment of MpGs.
They were rated at 15 City, 23 HiWay, and certified to tow 7000lbs.
[The Fleetwood's longer wheelbase may have something to do with it.]

V92 Caprices and Roadmasters had 2.93, a 'standard-spec' 4L60E, and shift tables and line pressures written for MpGs to the detriment of towing, thus an advisory to put the shifter in 'D' if needed to avoid 3-4 hunt-shifting.
They were rated at 17 City, 25 HiWay, and certified to tow 5000lbs.

Fleetwoods with 2.93 had a 'standard-spec' 4L60E, and shift tables and line pressures identical to V92 B-cars, yet were only rated to tow 3000lbs.

9C1 Caprices with LT1s had 3.08, a 4L60E built to a 'pursuit' spec, and unique shift tables and line pressures accounting for both MpGs at low throttle angles and the likelihood of pursuits.
I suspect their ratings were 17 City, 25 HiWay, and 3000lbs[, but I can't be sure].

Don't know about B-cars with 2.56 or L99 …
I am pretty sure it is 5000 for LT1 9C1s, and the owner's manual says to tow in D.
A 9C1 Caprice owner's manual would be a precious [comm]oddity …
While 3.08 is always better than 2.93 for these cars, I was under the IMPRESSION that the lack of a [email protected]$$ mech fan was the formal technicality that prevented the 9C1 from a tow rating of 5000lbs?
No matter, I'd rather tow with a 9C1 with electrical fans, than a V92 with a mech fan any day.
What I do is wire a switch on the electric fan cars so I can turn on BEFORE the motor gets hot such as a backup in the summer or getting ready to pull a hill.
When does the stock fan come on? Like 220°F?
Why roast the motor then cool it down? With the mechanical fan it just stays cool.
Reprogramming the fans' on thresholds does the same thing without additional wiring hardware.
OEM electric fans don't come on til 225°F & 232°F, which is bat$h!t ridiculous considering that the mechanical fan NEVER allows that to happen. Some people haven't figured this out yet [after 20 years].
Tuners usually lower the fans' on thresholds to 203°F & 212°F for use with a 180°F thermostat, or 185°F & 194°F with a 160°F tstat.
GM advertised the Fleetwood V4P as being able to tow that and do it in overdrive.
Amended.
Most of us have the good sense to have a 160°F thermostat and a PCM tune with lowered fan turn on temps and adjusted shift points and increased pressure for crisper shifts as well as an aux trans cooler(9c1).
If you don't at least have the trans tuned, you should install a Transgo HD2 kit. There is a Sonnax kit also.
I wouldn't start towing with the stock setup anyway. The trans is the weak link in all of this.
Adjusting the shift points and line pressures is the other critically important reason to have the pcm reprogrammed.
Some people haven't figured this out yet, either …
 

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The Roadmaster is rated for 7000 lbs if you disable the air shocks.
 

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The Roadmaster is rated for 7000lbs if you disable the air shocks.
No such thing as a 91-96 Caprice or Roadmaster (similarities outnumber differences here) with an L05 or LT1 spec'd from a showroom floor to tow 7000lbs.
Only Cadillac Fleetwoods, and then only when equipped with RPO Package V4P, are rated to tow 7000lbs.
Caprices and Roadmasters, and then only when equipped with RPO Package V92, are rated to tow 5000lbs[, not 7000lbs].

Anyone with a Roadmaster [or Caprice, for that matter] who can plug their VIN into
http://www.compnine.com
and come back with an RPO stipulating to a 7000lb tow rating should do so, it would be the 1st instance of its kind.

Every error disseminated on the ISSF, diminishes this forum's value.
 

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Sorry Marky, I wasn't completely accurate.

In order to tow 7000 lbs with a Roadmaster you need to do a couple things.

1. Have the V92 towing package
2. Disconnect air shocks (pull fuse)
3. Inflate rear tires to 35 PSI for better load rating
4. Use a weight distributing hitch
5. Use two sway bars
6. Adjust the hitch so it's about 12% of the total weight

It states all of this in the factory owners manual. I've attached a copy of the relevant pages for reference.

I take misinformation seriously, but you're right, I should have stated my source. I'm new here, not new to towing or engineering.
 

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1stly, well done; most newbz are too narcissistic to understand that accurate info is more important than anyone's feewings, especially the emotions of someone who can't be bothered to try research before re-asking a question that no longer requires anyone's participation to answer.

2ndly, well done; you actually have some proof, and something NEW to bring to the table after 2 decades.

3rdly, here come my weak counterarguments …

Now that we've all seen what a Roadmaster owner's manual has to say, I want to know why a Caprice owner's manual doesn't say the same thing.
If a Roadmaster V92 and a Caprice V92 are functionally identical, why doesn't a Caprice owner's manual let me in on the secret steps required to upgrade a V92 Caprice from 5000lbs to 7000lbs?
(This would be the time for someone to whip out a Caprice owner's manual & quote any relevant info.)

V4P: TRAILER PROVISIONS, NOT TO EXCEED 7000 LBS
V92: TRAILER PROVISIONS [the RPO description itself says nothing else, regardless of where I look, can't find a specified weight rating]

By the way, my 94 Caprice owner's manual says, on page 143, "It should never weigh more than 5000 pounds." (Sorry I'm photographically retarded.)

So if a V92 Caprice and a V92 Roadmaster are functionally identical,
Why would GM keep the secret from Caprice owners? (The price difference?)
Why would GM give the Fleetwood V4P a 4L60E with unique hardware specs, unique line pressures and shift points that look like a Tahoe's Tow/Haul button was permanently pressed, and 3.42 to earn a 7000lb tow rating?
Why not just buy a Roadmaster [but not a Caprice] V92 with run-of-the-mill 4L60E hardware specs, line pressures, and shift points, and merely 2.93, yet somehow still earns a 7000lb tow rating, provided the shifter is in 'D'?

Something doesn't add up.
(For what it's worth, V92 B-car line pressures are simply inferior to V4P line pressures, which makes me think GM simply printed a mistake, like 94 L99 wagons, or 91 sedans with standard 205/75R15 tires - not typos, mistakes.)

3-part Question:
What's the GCWR of a V92 Caprice?
What's the GCWR of a V92 Roadmaster?
Whats' the GCWR of a V4P Fleetwood?

You guys with 96 Caprice & Roadmaster owner's manuals, whip 'em out; I'm afraid I'll believe a 96 owner's manual over a 94's any day.
Or, in the alternative, if KatShot is still out there, maybe he can help to clear things up?

Anybody got a 94 Cadillac Fleetwood owner's manual?

Also, betcha the 96 manuals say 'less' than the 94 manuals …
 

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Ah yes, my anal engineer is still in there. Even though I haven't practiced engineering in oh, 18 years?

Anyhoo...

Here's my thinking on towing.

I believe there are a couple critical specs that should never be exceeded.

Tongue weight vs. hitch specs
Tire weight ratings
Axle ratings

All these are measurable and have what I consider real specs associated with them.

I think most tow ratings are some mythical mix of engineering, marketing and legalese.

For example, why has every minivan since the first 2.2L Chrysler had a 3500 tow rating, when most modern minivans have more power, better suspensions, and weigh more than my Roadmaster? That's marketing, to get you to buy up to a truck.

I do believe that if you tow a lot, you'll blow up your transmission eventually. We put a shift kit, bigger solenoids (?) and a bigger cooler on ours when we rebuilt it.

But otherwise, once you're really moving, weight isn't nearly as critical as aerodynamics. Drag exceeds weight very quickly, but nobody can measure drag, so we don't have a spec for it.

Our vintage trailer is pretty streamlined, plus it sits a lot lower than modern trailers. It has 2 axles, brakes on both axles, and a properly set up WD hitch. We have towed it over 10k miles with no issues.

But then it's only about 5500 lbs give or take 100 when loaded, so I'm not really that far over the standard spec. And the more critical tongue weight is within spec.

There's a lot that goes into towing, it really is fascinating. And complicated. I'm really curious to see how ours feels compared to the tall, tippy, stiffly sprung Tahoe Z71 we're replacing.

Good discussion!
 

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Yes there is a lot that goes into towing.I've also towed my vintage Chevy's for many years,but always with a 2 wheel drive Suburban w/4.10 rear gearing.Always been a pleasure.

I looked up the tow info using my 96 B4U/LT1 Caprice owners manual.States the 5,000lbs,the 12% max tonque,but no where can I find anything that would indicate I can pull a heavier than 5,000lb load,like the 7,000lb listed in the RM owners manual example above.
I also could not find a GCWR spec from GM for my Caprice.Only the door jamb GVWR(vehicle,passengers,load,fuel) and GAWR's for front and rear.
I took a few pics below. Good question points being raised here. Jim
 

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