Suburban Questions-looking to purchase soon

[BBslider001]

First off, really great forum and some really nice builds on here! I am glad to have found it.

Well, I am looking at purchasing a Suburban in the next month or so and I have some questions. I will mainly be using it for daily driving, some exploring, and towing my RV. My main question is, does anyone tow with their rigs? If so, how much weight? I am looking at the older body styles (89-91) and leaning towards the 5.7 for reliability and fuel efficiency. I am just afraid it will not be strong enough to pull our RV the few times a year we need to use it or take it somewhere. It weighs 8500# loaded, so I am just not wondering if I might need to consider a 454 instead. Now I will be getting the 3/4 ton chassis either way for the stronger axles and suspension components. I am hoping to find one with a mild lift and I will be adding airbags to it myself to compensate for some of the weight. I have a ton of experience towing bigger trailers so i don't need an education there, but definitely need some input on the Sub for towing/hauling or any other things I may have forgotten about.

Also, what about reliability between the two engines? I know the 5.7 TBI is extremely reliable, but what about the 454? I considered the 96-99 era just due to power and the Vortec deal, but I like the older body styles and interiors so much better. Just have so much more soul, but anyways....thank for any input on this and please feel free to comment on anything else I may have failed to remember or inquire about. Mahalo!!

 

[tatuedrednek]

The 5.7 is great for a small trailer or camper, but if yours is that heavy, I'd consider a 7.4. It will eat you alive in fuel, but it will get the job done. I've worked on Chevrolet engines for all of my adult life, and reliability wise both engines are similar. I had a 94 3/4 ton truck with a 7.4 and it pulled my little 18 foot camper like it wasn't even there!

 

[warrpath4x4]

from my experience the the 454 is just as reliable an engine, the details are in the maintenance.

really so much plays into factor on fuel mileage between the 2 engines, gears, tires size and width, transmissions, if your only going to tow a couple times a year and dont mind having to slow down pulling hills then id say the 350. if you want more power for pulling the hills then go 454, but your daily driving mileage wont be as good (of course ive seen 454's do better mileage than 350's but its all in how you build/tweak them).

now my 383 stroker in my blazer has plenty of power and gets 15mpg and it needs a tuneup which i ordered parts for so i hope to be able to pull another 2mpg or something.

 

[Revco]

My neighbor has a '92 350-powered 3/4-ton 4x4 Suburban and pulls his dirt track car. He "claims" he gets 20mpg empty, but I call BS. I don't think he knows how to to math, must be all the driving around in circles. Anyway, my '93 454-powered 3/4-Ton Suburban pulls my 18' steel floor car hauler with a mid-size vehicle just fine. But it lacks the towing power I desire. Maybe I've just been spoiled with my previous Cummins 12-Valve diesels that could pull anything effortlessly. Even my 351-powered F-250 regular cab 2wd pulls 10 times harder than the Suburban. The weight of the Suburban is the downfall... my cousin had a '94 Chevy 2500 Regular Cab with the 454 and it would pull a '32 Gooseneck with 2 Jeeps on it easily. Same engine, same basic package, but much less weight than the Suburban.

 

[Keitha]

You may already know this, but you can not get a 454 in a 4x4 in <1991 Suburbans.

The 350ci will get the job done, but you will be crawling up some hills. Gearing will help a bit, but the motor just does not have too much power.

 

[FellowTraveler]

From Gm up-fitter manual.

96/99 c2500 burb 7.4 ltr w/3.73 rear will just tow the 8,5k trailer borderline.
" " w/4.10 rear will tow 10k.

96/99 K2500 burb w/7.4 ltr 3.73 rear will tow 8k trailer.
" " w/4.10 rear will tow 10k trailer

Suggest additional engine oil cooler and transmission cooler if vehicle is not equipped w/total tow package.

 

[goin camping]

OP, I'm in SoCal too so I know if your towing out of town there's some big hills to go over.

I have an 02 3/4 4X4 burb with the 8.1. Our trailer is 7k pounds but the burb pulls it as well as the Ford PSD did. I go over the Grapevine or any of the other passes and mountains at the speed limit without the engine straining.

Without the trailer I'm at 13mpg and with it 11.5 mpg.

Good luck

 

[BBslider001]

You may already know this, but you can not get a 454 in a 4x4 in <1991 Suburbans.

The 350ci will get the job done, but you will be crawling up some hills. Gearing will help a bit, but the motor just does not have too much power.

I did not know that. Thanks! That may help quite bit. Costa Mesa? Like that area....good logging at Bolsa Chica.

 

[BBslider001]

Well, I think it looks like I am going to be looking at the 96-99 models, which is kind of a big bummer. I need the towing capabilities though and the Vortec 7.4 seems to be doing well for those who own one and really use it. At least I'll have better fuel efficiency and comfort. Really appreciate the input. I now gotta change my shopping criteria.

 

[bob91yj]

It's not so much the going that is the issue with the older 'burbs, it's the stopping that I always hated in my '89 454 3/4 ton.

That is good info on the 454 only being available in 2wd for that generation.