Should my truck tow 4k lbs better than it does?

[Fast Eddie]

My 94 k1500 seems to struggle when towing my boat. It has a 350 (with almost 40k on it), new tranny (which actually helped alot), and a 3.42 rear. I'd assume it would tow much better than my v6 yota 4runner, but only slightly.
So far I've replaced the cap, rotor, plugs, wires, and fuel filter. When I bought the truck the owner had already put flow-tech headers on it, a catback exhaust, a throttle body spacer, and a k&n airfilter.
I'm not getting any codes.
Besides checking the timing, what else should I do?

Thanks,
-e

[John DiMartino]

FAst Eddie,I had a few 350 TBI GM trucks, all were a dissapointment towing anything at all. Just take it slow and you'll be happy.I do not like going slow,so I wasnt happy at all with my trucks power.The performance your getting is about right.I had a 94 Chrysler Town and country AWD Minivan for 3 yrs,it was a better tow vehicle than my much bigger 94 Chevy Z71 excab K1500.In every respect it had more towing power,stayed in OD locked up even on moderate hills,and controlled the trailer better. My k1500 was gutlesss,and I had the 3.73 rear,and 350/auto combo. I I have a 1500lb 2-See doo 's and trailer,the mountain to the lake would pull my truck down to 55mph wide open ,and the trans would drop to 3rd. The minvan held 66-70 mph up the entire hill,in 3rd gear. i used the Van whenever I towed under 3500lbs because it towed so much better. After 3 yrs of frustration towing,,I fixed the problem,when I bought my first Cummins diesel.:D .

[CraftyBigDog]

I would put different gear ratio in it like 4:10 it would make alot of difference, those are highway gears!

[JohnnyU]

Honestly if the headers are the AfterBurners, I think you may have a backpressure problem. The torque curve may be moved too high, causing the peak torque to start coming on at a higher rpm, thus it has to downshift to accelerate. I'd almost bet money that if you replaced the headers with shorties or just factory manifolds, you'd notice an increase in low-end torque and towing power...

$.02

[Fast Eddie]

John,
I've wanted a Cummins for a while now, I just couldn't ever justify buying one. :(

Crafty,
It's a 4x4, I think the cost would be somewhere around $1000. Not only that, but I don't think a 4.10 gear would fit in the housing.

Snowy,
What headers would you recomend for lowend torque?

[JohnnyU]

You could use 4.10 in the 8.5" rear and 8.2" front diffs, infact, it wouldn't ba a bad idea if it was going to be a work truck, but if you are taking long highway trips, I'd keep the 3.42 or 3.73:1

I would get a good set of shorties, Gibson makes a good product, as does Edelbrock. I have the AfterBurner headers, they are alright, but I will not buy them again. I think you could put the factory manifolds back on and still be at the same performance level, if not better for towing, since you have the other bolt on upgrades. The best header I have ever seen is made by Doug Thorley, it's a tri-Y design, pretty slick....

The ultimate engine add-on would be a set of heads, the stock TBI heads are pretty bad, if you;ve ever looked down the intake port, you'd know what I mean. The TBI trucks don't respond that well to bolt-ons, they like internal changes, Comp makes a good replacement cam that is compatible with the computer, and Edelbrock makes a Power Package, chip, cam, heads and intake, they all are tuned in conjunction with each other to give you the optimum power gains.

[Ohiosnow]

I had the same truck 1994 K1500, 5.7 TBI, Auto, Ext.Cab, short bed, LT265-75-16's but with 3.73's & it towed well plus would smoke THEM as long as I held the pedal to the floor :burnout

In the 6 years I had it I towed a bobcat at least 12 times over the years & did think it had trouble with that ;) but it towed my 21' Boat with no problems. It's 70 miles to the Ohio river thru the hills on 2 lane roads, I never thought it struggled but it did downshift sometimes when I would floor it to pass someone :rolleyes: or stay at a steady speed going up a steep hill.

I sold it to a relatives brother-inlaw who still plows & salts with it & he can't get over how strong it is out of the hole :burnout & it's still stock. And with the original trany never rebuilt or the engine :eek: I think it has about 85,000 miles on it now. I guess I had a good one :D He's thinking of putting in a superchip just to have more fun :cool:

[sonjaab]

EDDIE........I have a GM 94 towing guide handy.

It shows a max. trailer weight of 6000 lbs. with a 350
auto., 3:42 gears, 4x4

So ya gotta figure your about at max or over GVWR of
11,000 lbs. with truck, trailer, passengers and extra stuff........................geo

[Fast Eddie]

Originally posted by sonjaab
EDDIE........I have a GM 94 towing guide handy.

It shows a max. trailer weight of 6000 lbs. with a 350
auto., 3:42 gears, 4x4

So ya gotta figure your about at max or over GVWR of
11,000 lbs. with truck, trailer, passengers and extra stuff........................geo

4000 lbs is a liberal estimate of what the rig with trailer, fuel, and gear weighs. It's just a 17' center console (dry weight is 1500lbs). Typically I only have myself and one other passenger in the truck.

Ohio,
I can light the tires up in a turn, that's all.

The more I think about it the more I'm leaning towards selling it and buying a Dodge with a cummins. I suspect the boat is going to grow at least another 6-8' by the end of 04' to mid 05'.
Like I said the boat is ony a 17'er, I'd think I would barely be able to tell it's back there even with the 3.42. rear, it just doesn't seem right..

[Staley52]

I agree you should be able to:burnout with that truck and mismatched add ons could be a culprit goodies that move the power band in differant directions fight each other
I have seen trucks that towing power went down with headers also something to try is
:greenange "fix" the cat
and have the computer checked there may a chip in it also and may have problems or put it on a dyno with a gas analizer to check the actual performance this truck is not obd2 and yuo may have a bad o2 sensor or other items that the ecm thinks are ok but that truck should do very good at the work you are doing

[76chevyman]

That throttle body spacer doesnt help on the low end. It only helps at the top of the power band. Ive towed a Bobcat with a 1500 suburban and it was fine other then the bumber was on the ground LOL

Rich:burnout

[Fast Eddie]

76,
Should I yank the TB spacer?

Thanks,
-e

[JohnnyU]

Eddie, I wouldn't yank it, I didn't see any decrease in low-end when I put mine on, I don't think it would be worth the effort to remove or the cost of the new gasket.

I think the problem lies in the headers.....

[Fast Eddie]

Originally posted by SnowyBowtie
Eddie, I wouldn't yank it, I didn't see any decrease in low-end when I put mine on, I don't think it would be worth the effort to remove or the cost of the new gasket.

I think the problem lies in the headers.....

That'll be resolved soon... Hopefully I'll have a set of Edelbrocks for my motor to breath through by the end of the week..

I'll either be praising or cursing you next week... just kidding ;). I'm sure the fellow who owned the truck before me saved money on the rebuild by putting the flowtechs in instead of new exhaust manifolds in. I'm sure a $130 set of headers don't go through much of a design and developement process anyway..