Teach me suburbans

Now after seeing the diesel suburban that just sold over in the classifieds I have the urge to buy one...

I have been looking for a 4x4 truck/hauler of some sort.

How much can an automatic suburban pull? I would like one with the flip down rear tail gate. Looks like those are the earlier ones.

I understand these are a HUGE truck but how are they on gas? Can EFI be fitting without much trouble from the tbi trucks of the early 90s?

This one is about an hour for me on CL and boy am I drawn to it. The seller says that something is wrong with the trans.....1st and 2nd are fine but when in drive and going to 3rd or 4th there is nothing.

If you have that 700r4 beefed up on the rebuild it likely needs, and mount a bigass trans cooler, it will pull quite a bit. I've always thought the big block 3/4 ton model with the TH400 3 speed is the one to get, gas mileage be damned.

Mine was a lot of fun even though it was rusted out. I don't remember the gas mileage but mine had a 350 engine in it. I wasted a bunch of money on having the engine rebuilt for more performance but the mechanic wasn't worth a damn. I still liked driving it though.

pull 7k with a built 700r4? Or swap in a 4l80e?

I would like to have the ability to pull a 2 axle trailer with a car/truck up to around 5k lbs. Normally MUCH smaller lighter pulls but I wouldn't mine some head room.

Can you fit a 4' sheet of plywood, drywall, etc between the wheels in the back?

With the back seats folded, 4x8 sheets of plywood fit with about an extra foot of length to go. I know that personally.....

Bobzilla wrote: With the back seats folded, 4x8 sheets of plywood fit with about an extra foot of length to go. I know that personally.....

indeed. we carried about 40 sheets of 1/2" drywall in my 94.

woah, 1' left to go with the doors shut?!?!

That is awesome!

What sort of econ can I expect stock? If the trans is bad I am wondering if rather than build a 700r4 would it be better to sell the engine and swap in a LS and 4l60e or 4l80e with a 5.3 or 6L.....

Read the book "Rivethead." No, seriously. The Suburban plant had the worst quality in the entire GM empire.

Mine was a 1988 3/4 ton 350ci TBI and it was an astounding piece of engineering snot. As an American I'm ashamed that was sold as recently as 1988.

David

Had a 1990 TBI big block model. Didn't end up needing to do any heavy towing, previous owner used it to pull his boat. Mileage was around 12 mpg, but it could probably pull anything short of a singlewide mobile home. Previous owner had added an extra fan for the trans cooler.

I agree that the 4 speed auto isn't much for towing; it's really more of a passenger car tranny. A TH400 or 4L80E would be a much better towing option. (The 4L60E is an electronically shifted version of what it's got now.)

Depends on what gearing the axle is.

I have 33"s and 4.10s with an SM465 85 3/4 ton (see frankenburban GRM build thread)

At 75mph I am around 3100rpm with a SBC TBI. 10-12mpg pulling or not but I typically tow/highway at 60-65mph

Sure some of the newer vehicles can tow alot but the suspension and drivetrain on these things are meant to tow nearly anything you can with a hitch. (non 5th wheel style trailers/campers)

that and parts are dirt cheap, easy to fix/service. So if you take it as a hauler, who cares if it breaks down. every little hillbilly auto parts store in town is going to have chevy treeeee fiddy parts and everyone knows how to work on them. (worst case scenario)

You can also sleep in it when you fold the back seats down (if your 6'+) and still have room for all your gear.

DWNSHFT wrote: Read the book "Rivethead." No, seriously. The Suburban plant had the worst quality in the entire GM empire. Mine was a 1988 3/4 ton 350ci TBI and it was an astounding piece of engineering snot. As an American I'm ashamed that was sold as recently as 1988. David

The one Dad had he purchased with 215k miles and a stripped interior from the front seats back and a blown 700R4. Installed a GM Cert reman, pulled entire trees (60' long locust trees) out to cut them up, hauled 800-1000 lbs of concrete and plywood/lumber for 3 years etc. When he sold it (after 10 years of abuse aka ownership) everything still worked. The guy that bought it used it for 3 more years to haul rusted 73-87 chevy trucks home to do body work and then flip. When HE sold it, it was pushing 420k miles and still ran great and the trans was still kicking.

The 2 biggest issues that truck ever had was starters (went through one about every other year) and a left rear axle seal (14-bolt FF) that had worn the axle shaft so it would not seal worth a damn and constantly coated the 13" rear brake drum with oil and would make it lock in an instant. Ok, 3..... rust.

This may be the only picture we have of it left:

It was a 1984 with a 6.2/700r with 1T fr/rr axles with 4.10 gears.

In reply to Bobzilla:

the only big difference between 1t and 3/4 is that the 1t got a dana 60 for a front axle and the 3/4 is a 10 bolt.

Well, this truck was actually a K10 originally. At some point the PO swapped in the D60, 14bolt ff rear, did a spring flip and added a 6" block in the rear. Frame and body was 1/2T, running gear and brakes were 1T.

EDIT: K15, it was a GMC.