5er's and Sonoma's: What to pull????

[dugear]

Add me to the 'more than confused' group. Here's my numbers and the question is "What 5er can I pull with this unit?".

2000 Sonoma, 4.3L, 4x4, ext cab, auto, 190 HP, HD suspension, Gear ratio 3.73, WB 122.9"
GCWR: Can't find it but have seen other posts claiming 9,000 and 9,200 lbs.
GVWR: 5,150, Curb Wt = 3,765, Payload = 1,385
GAWR: F = 2800  R= 2700
Tow Rating: 5,900

Here's what I've calc'd and would appreciate feedback. Yes, these are calcs to the max!

GVWR (5150) - Curb Wt (3765) - Passenger's (350) - Gas (150) - hitch (100) = Max Pin Wt (785)
Payload (1,385) = Passenger's (350) + Gas (150) + hitch (100) + Max Pin Wt (785)
Max RV wt (5,233) x 15% = Max Pin Wt (785)
GCWR = GVWR(5,150) + 5er(5,233) - Pin Wt (785) = 9,598 (Close or what?)

The UVW of the unit I am looking at is 4,150 which includes 257# of water and 59# of propane.
That would seem to indicate about 1,100 pounds to spare.

OK, let me have it! Thanks in advance.

 

[Gary RV_Wizard]

I think you (and GM) are being optimistic on the tow capacity.  A dozen years ago I had an indentically powered Sonoma Extended cab short bed and towed a 4500 lb fiver in the Florida flatlands.  It moved it, but it struggled to accelerate at highway speeds, could not sustain overdrive even on smooth level roads, and never would have made any sort of grade.  Swapped that truck for a Dodge Dakota with the 5.9L V8 and got happy again.  That Sonoma (a 1994) got about 30 less horsepower from the 4.3L V6 than more recent ones and may have had a lower ratio rear axle, but I still think you should stay well under it's alleged rating.

Any small displacement engine will lack grunt for towing and the 4.3 is, well, pretty small. Carl usually recommends staying 10% under the tow rating for East Coast trailering (20% in the West) and for this small an engine even that may be stretching it.

 

[dugear]

Thanks Gary,

Ya, I'm pretty much on the edge there. After reading tons of other posts, it is pretty apparent I would be quite underpowered. Oh, I am also in the 'West' so that 20% becomes a big factor too. Long story short, gotta keep the 5er so will be upgrading the truck to fit. Thanks again.