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Suburban 1/2 vs 3/4 tow rig

I struggled with buying my 8.1 2500 burb with 4.10s. My dad told me that I'd use it more than I thought and it'd be so much nicer than a 1500. As always, he was spot on. Now the only struggle is gas prices.
 
I don't think an 8.1 burb gas mileage is much worse than say 6.0 or 5.3 in a like chassis.
I know mine get 1/2 again better than my 77 sbc k20.
 
Rear end Gear ratio's are very relevant for towing.... Brakes are an issue.....

?? 14 bolt full Floating rear end ??? Wow, gas will be consumed harshly for a commuter ride...

What is the GVW of the suburban your looking at? It may have the bigger rear end, if it had a tow package...

Springs are relatively cheap.... a 9'5" rear end would be the better choice for fuel consumption.

If its priced right & the tin is in good condition etc....go with it & change a rear diff if needed.
 
3/4 tons went to the semi floater in the early or mid 80's. The earlier trucks got a 14ff with the correct spring spacing.
The later Burb squares also offered the 14FF even after the 14SF came on the scene in 81.
It was an upgrade suspension option package on the C/K 20 Burbs ( something like C6P RPO code or something similar).

For the OP add another vote for a 3/4 Burb of any flavor and like the others have said they ride really well - nothing like a pickup with an empty bed that rattles teeth and kidneys. The bigger brakes alone are worth it regardless of 350 or 454 ( 454 being preferred of course but that means 2WD in 3/4 squares….)
Find a good 87~91 TBI 350 K-20 Burb with 4.10’s and if it’s a 14SF then swap it out for a FF with the 13” brakes ( not all FF’s came with big brakes ) and let it ride.
If 2WD are still on the table find a 87~91 C-20 with a 454 and have no towing worries - bonus points on the 91 model year with a 4L80E O/D trans.
 
I don't think an 8.1 burb gas mileage is much worse than say 6.0 or 5.3 in a like chassis.
I know mine get 1/2 again better than my 77 sbc k20.
For same chassis, we all know the bigger engines consume more fuel than the smaller ones. Except while towing, where the big cubic inches sometimes beat the small blocks for MPG. As we all know, the BBC gets consistent mileage regardless of conditions, while SBC sees a lot of range of MPG between empty/towing/etc.

But yeah, a mid 2000's 8.1L Sub will match the MPG of 1980's Sub with SBC for normal driving.
Rear end Gear ratio's are very relevant for towing.... Brakes are an issue.....

?? 14 bolt full Floating rear end ??? Wow, gas will be consumed harshly for a commuter ride...

What is the GVW of the suburban your looking at? It may have the bigger rear end, if it had a tow package...

Springs are relatively cheap.... a 9'5" rear end would be the better choice for fuel consumption.

If its priced right & the tin is in good condition etc....go with it & change a rear diff if needed.
A larger rear axle has little impact on MPG - basically the same as any other weight gain. Gear ratio has an impact, of course. Feel free to post actual data that contradicts if you can find some.
 
Full Floating rear ends are turning more rotating mass... More unsprung weight.... And the gear ratios are very.limited.

I have a 14b FF in a K30 mason dump truck. Easy math 10 mpg.

General Motors must have had a sound reason to build 3/4 ton semi floating rear ends
 
I have a 14b FF in a K30 mason dump truck. Easy math 10 mpg.
Please post math.

(no, not miles driven/gallons of gas burned, but the mathematical effect of another 100lbs in the rear axle). We can allow for another "K30 Mason dump truck" of the same size, but with a smaller rear axle installed.

14 bolt factory ratios: 3.23:1 to 5.38:1
 
Road trip time!!
When I recover financially from moving Mom in I'm going to find a nice burb.
Thats cheaper than fixing mine.
 
Looking at picking up a suburban to use as a driver and occasional tow rig butwanted to get some advice from people on here who have used them.

I occasionally buy a car and use a uhaul transport (last tow was 90 gmc jimmy) but I also have a camping trailer 21.5 feet and 3000lbs. I’m torn between if a 1/2 would be okay or I need to step up to a 3/4. I live in Texas so flat but tend to travel to the east coast like Virginia and North Carolina as I have family there.

I found a 89 350 with a tow package and 3.42 gears. Also looking at a 85 454 3/4 ton but it’s double the price. It would see rotation as a driver but maybe tow 10-12 times a year so I’m wondering would the 1/2 get by fine and be a comfy ride or should I plan on just go 3/4 to be safe. My biggest concern is so have a 94 f250 460 currently and it has factory heavy duty suspension so the ride sucks. Looking to pick something up then sell it as I hate the ride
I have owned and driven:
1/2 ton suburban 350 1989
3/4 ton suburban 350 1985
3/4 ton suburban 6.2 turbo diesel 1984
1 ton crew cab 350 1980
1/2 ton suburban 350 1997
3/4 ton suburban 454 1998

I towed with every one and after towing with the 3/4 ton and 1 ton I will never tow with a 1/2 ton.
350 was ok but my 6.2 turbo diesel was better, until I got my 1998 454.
It's the only truck I drive or tow with now until I finish putting the 8.1 in my 1989 suburban.
It even got better mileage than my 1/2 ton with the 350 loaded or empty.
They both even had the same gears, 4.10
 
Still trying to sell my early bronco to get the funds for the suburban. But hopefully soon. Have a few interested people but no one showing up with cash. Was hoping to sell it then my f250 (hood axle hailer) but have a friend who might want my f250 soon.

I get a 90s 454 suburban makes more sense but I just think they feel too new. I would prefer a 78 suburban but feel the 85-91 are new enough yet have a old feel. My daily driver alternates between a 78 bronco and 90 jimmy. The jimmy has been in my fleet for maybe 6 months and really enjoying it so though a similar suburban would be great over the rough f250. Also have a 68 mustang and 76 corvette, you can see my mpg is not crazy essential. Also I work from home so no commuter of 30-50 miles a day is needed. More like 10-20 max for dinner or groceries. Also if I need to save gas I have a Harley backup haha.

Still looking at the 91 gmc but also found a 85 Chevy that is the burb version of my 90 gmc jimmy. It’s still 1/2 ton but I would plan on 14 bolt rear and a Dana 44 front with 8 lug, wilwood front brakes, and either 3.73 or 4.10 gears. The 1/2 and 3/4 use the same wilwood caliper so I cannot see that much brake difference so just axles and save up for a 4l80 swap or beefed up 700r4. Then maybe a 383 with a proflow for a solid puller
 
Are you set on square-body? Any interest in a later 90's 6.5TD 2500? For a ready-to-tow comfy Suburban, a factory 8.1L rig from the 2000's is hard to beat.
I get a 90s would make more sense just too new in my mind
 
Still trying to sell my early bronco to get the funds for the suburban. But hopefully soon. Have a few interested people but no one showing up with cash. Was hoping to sell it then my f250 (hood axle hailer) but have a friend who might want my f250 soon.

I get a 90s 454 suburban makes more sense but I just think they feel too new. I would prefer a 78 suburban but feel the 85-91 are new enough yet have a old feel. My daily driver alternates between a 78 bronco and 90 jimmy. The jimmy has been in my fleet for maybe 6 months and really enjoying it so though a similar suburban would be great over the rough f250. Also have a 68 mustang and 76 corvette, you can see my mpg is not crazy essential. Also I work from home so no commuter of 30-50 miles a day is needed. More like 10-20 max for dinner or groceries. Also if I need to save gas I have a Harley backup haha.

Still looking at the 91 gmc but also found a 85 Chevy that is the burb version of my 90 gmc jimmy. It’s still 1/2 ton but I would plan on 14 bolt rear and a Dana 44 front with 8 lug, wilwood front brakes, and either 3.73 or 4.10 gears. The 1/2 and 3/4 use the same wilwood caliper so I cannot see that much brake difference so just axles and save up for a 4l80 swap or beefed up 700r4. Then maybe a 383 with a proflow for a solid puller
The caliper is the same but the disc is bigger, so more leverage to slow down the truck.
As for upgrading a 1/2 ton, I put 8lug front d44 and a 14 bolt full floater on my 89 1/2 ton suburban and put 3/4 ton springs and I am putting an 8.1 with an NV4500 in it.
Not much left of the original but I can't find the combination I want so I am building it
 
The caliper is the same but the disc is bigger, so more leverage to slow down the truck.
As for upgrading a 1/2 ton, I put 8lug front d44 and a 14 bolt full floater on my 89 1/2 ton suburban and put 3/4 ton springs and I am putting an 8.1 with an NV4500 in it.
Not much left of the original but I can't find the combination I want so I am building it
Good to know! If i cannot fina 3/4 ton I will be on the hunt for a 3/4 dana 44 and 14sf. Maybe add some helper bags.
 
Good to know! If i cannot fina 3/4 ton I will be on the hunt for a 3/4 dana 44 and 14sf. Maybe add some helper bags.
The axles are the same, just the outer are different.
Change the hubs & rotors and mounting brackets over to 8 lug and your good.
 
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