Need some help pickin a BURB

[Leftcoastlax]

Hey guys, after much research on both this board and Pirate4x4, I think I've come to a decision on what rig I want to build. My goal is to get a rig that can:
1) Get me and my friends (sometimes more than 5) up to Tahoe comfortably with gear
2) Safely tow a 5k# ski boat up to 2 hours with no issues
3) Make it through the Rubicon in one piece, drive there and drive back
4) Cruise control, power everything and most importantly, AC

I've come to the decision that a 1988-1991 Suburban is the right rig for me. 4" lift in front with shackles and 1" zero rate in the back, 60/14 swap with 4.56's and a locker. A couple questions for you guys:
- I plan on running 35-37" tires; if my ultimate goal is to have 1-ton axles front and rear (most likely a CUCV set with 4.56' and a detroit), is there any reason to look at the 2500's? I know the 91's freakishly came with a 4l80e, but they are pretty hard to find.
- It's also pretty rare to find these rigs with cruise control that was there stock or still works. I know they were vacuum based, but can an aftermarket cruise control kit from jcwhitney or audiovox do the trick? I hear they can be a pain to install?
- I've heard good and bad things about the 700R4, I know I'm not towing anything too crazy with the burb, but is this transmission stout enough to handle mild-wheeling?
- Last but not least... I happened to come across a 88-91 burb that had QUAD CAPTAIN'S chairs! It was tits!! Was this a stock option? Possible to fab something up? Anyone done it?

I love checking out the page of built burb's in this forum and look at it daily for inspiration. I think I'm on the right track with this one and am really just waiting to pull the trigger on a rig that looks clean and is at the right price.

 

[rxinhed]

I suppose a Burb can do the Rubicon, just expect sheetmetal damage.

Cut fenders for the large tires?

 

[bfdiesel]

My cruise still works. As does my AC and all the power windows. Back in that time frame a gmc is likely to have all of that.

A lot of those things can be fixed if they aren't working, but know there are some out there that are still in functioning condition.

I personally think a 700r4 is useless.

 

[xpndbl3]

i would only consider a 3/4 ton. Just for the transmission and stouter frame alone. Better towing package usually, oil cooler, tranny cooler, bigger radiator, etc. All things that would add up if purchased separately. Got a pic of the captain chair setup or link to that add? Not factory but one of the conversion van companies could have swapped it in. I'm curious to see how it looks.

 

[Leftcoastlax]

i would only consider a 3/4 ton. Just for the transmission and stouter frame alone. Better towing package usually, oil cooler, tranny cooler, bigger radiator, etc. All things that would add up if purchased separately. Got a pic of the captain chair setup or link to that add? Not factory but one of the conversion van companies could have swapped it in. I'm curious to see how it looks.

What trans difference is it between the 2500 and 1500? I thought both came with the 350 and the 700r4 unless it was year 1991 with a unicorn 4l80e?

I was also under the impression that the frames were the same on both as well... am I missing something here? Where can I get the specs on these differences? I've seriously spent hours researching on both forums and never read that the 2500 came with a different transmission, towing package, radiator and frame. Links?

 

[xpndbl3]

No 2500 would be a th400, 1500 would be 700R4 or th350. Frame is thicker on the 2500 than the 1500 according to all the spec manuals I've seen. The other changes are all easily verified from an autozone, etc. The radiators are bigger, they would typically have a towing package, etc etc.


www.ck5.com should have a lot of knowledge on it as well. Definitely worth it to buy the 2500 series over the 1500 series.

 

[Keitha]

1991 3/4 ton is the tops - better transmission w/ the 4L80e, better PCM as it integrates the transmission controller (more important if you get into tuning your own chips). I have never seen any evidence that the frame is thicker on a 3/4 ton - if anyone has a "spec manual" that shows that, I would like to see it.
3/4 ton rear end (14 bolt semi-flooater) is plenty strong for 35" - 37" tires and it is lighter and offers more ground clearance than the full floating rear.

 

[Larry]

I have never seen any evidence that the frame is thicker on a 3/4 ton - if anyone has a "spec manual" that shows that, I would like to see it.

X2 There is no difference between ½ and ¾ frames in pickups or Suburbans of those years….suspension, transmission offerings and cooling systems yes…frames, no. The big difference was between the 1 ton and ½ & ¾ ton frames in pickups only, as there were no 1 ton Suburbans.

 

[BurbanAZ]

yea frames are the same size, id try and find the 4l80e if i were u i love mine its a great tranny, the 14bff is awesome and basically bomb proof but it does have some clearance issues. Id look for a 3/4 if i were you since they will be about the same price but you get better options.

 

[rxm6]

This guy makes upgraded 700r4s and non-electric 4l80es, just fyi.

http://www.transmissioncenter.net/highperf700r4.htm

http://www.transmissioncenter.net/4l80e.htm

 

[xpndbl3]

X2 There is no difference between ½ and ¾ frames in pickups or Suburbans of those years….suspension, transmission offerings and cooling systems yes…frames, no. The big difference was between the 1 ton and ½ & ¾ ton frames in pickups only, as there were no 1 ton Suburbans.

So, I was at Mtnman's property last weekend, and we started thinking about the thickness of frames, since he has a Chevy Grave Yard, we took some measurements.

All the measurements were taken on the right frame rail, in front of the front crossmember and behind the bumper.

There is some minor differences, I imagine it is the steel descrepencies.

1988 1/2 ton 2wd suburban -- .162

1981 4wd Blazer ------------- .164

1987 3/4 ton 4wd suburban --- .190

1988 3/4 ton 4wd suburban --- .203

1970's unknown longbed frame- .196

1977 2wd 3/4 ton suburban --- .208

1986 3/4 4wd DIESEL longbed- .231

1979 1 ton reg cab & chasis -- .236

1984 2wd 1ton crewcab dually- .224

1982 3/4 ton reg cab longbed-- .230

Clearly you can see in the literature even that the 3/4 ton frame is thicker :elkgrin:
.177 compared to .192

 

[Leftcoastlax]

wow... nice! Thanks for the info.

Definitely looking for a 2500, found one in San Jose. 350 motor rebuilt less than 10k miles ago, 202k on the trans and chassis. What do you guys think about the 4L80 having over 200k miles on it? Budget for a tranny service/rebuild?

Heater core out, front driveshaft not hooked up (due to 5" procomp lift). Local, has AC, has cruise, has barn doors, has a lift (most likely will get swapped out), has 35's.

He is willing to negotiate, I think it will prob go for around $3,000.

What do you guys think?

Just to confirm, 1988-1990 2500's have the TH400's? These lack overdrive correct?

 

[Larry]

So, I was at Mtnman's property last weekend, and we started thinking about the thickness of frames, since he has a Chevy Grave Yard, we took some measurements.

All the measurements were taken on the right frame rail, in front of the front crossmember and behind the bumper.

There is some minor differences, I imagine it is the steel descrepencies.

1988 1/2 ton 2wd suburban -- .162

1981 4wd Blazer ------------- .164

1987 3/4 ton 4wd suburban --- .190

1988 3/4 ton 4wd suburban --- .203

1970's unknown longbed frame- .196

1977 2wd 3/4 ton suburban --- .208

1986 3/4 4wd DIESEL longbed- .231

1979 1 ton reg cab & chasis -- .236

1984 2wd 1ton crewcab dually- .224

1982 3/4 ton reg cab longbed-- .230

Clearly you can see in the literature even that the 3/4 ton frame is thicker :elkgrin:
.177 compared to .192

Hhhuh!!!, who knew? We all learn something new every day. Great info!

Happy Turkey Day!

 

[Keitha]

Well I call that good evidence that the 3/4 ton frame is thicker, good find xpndbl3!

 

[89 suburban]

Thanks 4 the info