1/2 ton upgrade or find a 454 3/4 ton

[r67northern]

Hi all,

I'm inheriting s 21ft RV and want to put it behind an old square suburban. I've got a 90 half ton 4x4 with tow pac. I know I either need to upgrade the suspension to handle it (still leaving the TBI 350) or look around for a different square that is better for towing. Probably a 454 3/4 ton though I know that 350 versions of 3/4 tons are out there.

Any thoughts that might help me think about this? New rear leafs and load leveling seems like a minimum for the 1/2 ton. But she will still be low on power, but I've had her for so long it feels kind of bad to think about swapping her.

 

[crazy4offroad]

Helper springs would be an easy add-on, and they don't change the stock ride quality. You can get them up to I think 3,500 pound additional carrying capacity and they're not too expensive.
http://www.carid.com/1990-chevy-sub...5063521.html?gclid=COGS_d-_4sgCFQ-RaQod7-kDAQ
As far as helping the ole gal pull a bigger load you might look into stepping up the gear ratio in the axles. Not a quick or easy thing to do but the benefits are pretty great, especially if you're coming from like a 2.73 or 3.08 ratio.

 

[87scotty]

Agree^

 

[r67northern]

Helper springs would be an easy add-on, and they don't change the stock ride quality. You can get them up to I think 3,500 pound additional carrying capacity and they're not too expensive.
http://www.carid.com/1990-chevy-sub...5063521.html?gclid=COGS_d-_4sgCFQ-RaQod7-kDAQ
As far as helping the ole gal pull a bigger load you might look into stepping up the gear ratio in the axles. Not a quick or easy thing to do but the benefits are pretty great, especially if you're coming from like a 2.73 or 3.08 ratio.

I hadn't thought about a new gear ratio, she has a 3.73 in it right now as part of the 4x4 tow pac. 4.23 is the next step I suppose? So maybe helper springs and some simple TBI mods. I've looked into those a little bit, seems like a few hp can be pulled out without too much troubles tarting with an exhaust redo?

 

[crazy4offroad]

4.11 would be the next step, then 4.56. What transmission are you running?

Sent from wherever I am right now

 

[Georgeb]

Also, a weight distributing hitch. Next you need to be able to stop it. Trailer brakes and a brake upgrade like larger bore wheel cylinders in the back along with premium shoes, pads and rotors. Should work good that way. The tbi doesn't give you a great deal of room but exhaust, bumping the ignition timing up to around 10 deg and a slight increase in fuel pressure will help.

 

[r67northern]

4.11 would be the next step, them 4.56. What transmission are you running?

Sent from wherever I am right now

It's the 700r4 right now.

Good idea on the upgraded brakes too, trailer controller I've got in hand but need to install, same with the hitch.

Georgeb: I've actually pondered brake upgrade in general, those sound like good steps.

 

[Georgeb]

It's the 700r4 right now.

Good idea on the upgraded brakes too, trailer controller I've got in hand but need to install, same with the hitch.

Georgeb: I've actually pondered brake upgrade in general, those sound like good steps.

They work well. My 78 is a 1/2 ton with the tow package. I went to the larger wheel cylinders for the rear and premium friction material and that truck had very little issue stopping with considerable payload in it. now my 87 one tone with hydroboost......holy neck snapping brakes! I love it!!

 

[Lifted toys]

I would think a 1/2 ton anything much less a 350 would pull a 21ft camper with no mods all day. An upgrade to a 454 would be an extreme overkill, unless you just wanted one anyway.

 

[skysurfer]

How far are you pulling and is it flat or hilly? I pull a 20' pontoon just a few miles behind my Suburban and wouldn't want to go much farther. Boat plus trailer weigh about 2750 pounds and it's amazing how much more pedal it takes to maintain 50+ mph when you're pulling a barn door along behind you. I swear I can watch the needle on the fuel gauge drop. Stopping isn't an issue with the surge brakes, hydroboost, and wind resistance, but it sure is difficult to get going.

You'll have a fair bit of cash invested in gears since you're doing both axles. I'm already running 4.11s and they don't make up for the 350's lack of torque. Hate to see you spend a lot of cash to build what I already have and then wish you had just gone bbc.

 

[GTME94]

Mines a pickup and not a Burb but I'd recommend the big block. My boat and trailer are around 7k pounds. I've got a TH400 and 3.73 gears. It's not fast accelerating but it doesn't strain either. On relatively flat land I can go 60 mph no problem and pass slow traffic on the interstate. However I don't like to go much over 60-65 to keep it safe and keep the rpms down.

My ideal tow rig would be a 3/4 ton 4x4 burb with a big block.

 

[yevgenievich]

All depends on how quick you want to drive. A big thing to consider is that 3/4 ton used different cam for much greater improved torque in lower rpm range. I have towed up to 8k lb with my 91 V2500 (350 tbi, 3.73 gears) and was satisfied with performace. It is much slower than 97 crew cab with 454 I used to have, but sufficient. My v2500 works well with 75-80mph speed limit as it puts it in a good rpm range for overdrive(4l80e). Around 60mph with the weight and hills I keep it in 3rd

 

[shiftpro]

Don't do it with the 700r4, especially if it already has seen miles. I promise you will fry it.
Some 21' campers are absolute pigs and others are not so heavy. Hope you're is on the light side.
Having said that, do you have any mountains around there where you will be yarding your camper up? If your 700r4 is in good shape, like rebuilt with some better parts in it, and you have DEEEEP gears (the best way to run an over drive transmission on a heavy vehicle), and extra extra transmission cooling rigged up you could get away with it.

 

[jcmoyer2004]

Hey r67, if you're still looking for a 3/4 ton shoot me a pm. I may have one you'd be interested in.

 

[fussfeld]

how heavy is the trailer?