Should i keep or sell my '90 Suburban V1500 4x4 350 V8 with 700r for a '89 V2500 Suburban 6.2 Diesel

[blackandgold51]

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  I'm torn in between. I've been wanting to get a diesel Suburban after having two(on my 2nd one now) gas Suburbans. The first one was a R1500 1990 with a 700r4 and I'm now with my second which is a 90' V1500 4x4 with a gas 350 with a rebuilt 700r4. The gear ratio is where the engine reaches high rpms especially in 1st andshifts quick than the last suburban I had. Ok to make it short.... I saw this Suburban for sale which is a 89 V2500 6.2 rebuilt diesel with a 4x4 and 480LE Transmission. I've been reading and hearing that the 6.2 diesel is bad/good sluggish, good on fuel mileage. I don't tow as much. Only been a FEW times have I've towed and I towed LIGHT stuff if I had to. And I don't drive fast like a maniac. The suburban which is the 89 has good like new interior although the body does need paintbut that's about it. I wanted to install a diesel engine in my current (90 V1500) Suburban but I've been told to just sell it and get one with a 6.2 already in it. Should I sell for that one or keep what I have?

P.S The 89' Suburban 3/4 Ton 4x4 6.2 has a rebuilt engine and 4L80E trans . it's been took cared of. And the interior is like new condition. All it needs is paint on the body. The owner was in the process of making it into a show truck or " show truck" but he has no use for it and has other cars he"'s trying to get rid of. And premium gas(which I mainly use)here in new orleans is around 2.50 to 2.30 something a gallon while diesel prices is in the same area.

 

[jeff in co]

If you are thinking about converting anyways, I would at least look at it. Conversion can get a lot more involved and more unknowns while you do it. If you found a truck that is moreless identical (89-91), then it's probably worth it. The only advantage to the 91' 2500 is the introduction of the 4L80 tranny. I'm not familiar with the typical tranny mated to the diesel on, but if it's already in the 89' that's a great bonus.

Be sure to price a paint job if needed and figure that into the equation. A good paint job can be $3k-$5k I'm guessing......

I'd drive it and see how it performs. Worth a shot!

 

[blackandgold51]

If you are thinking about converting anyways, I would at least look at it. Conversion can get a lot more involved and more unknowns while you do it. If you found a truck that is moreless identical (89-91), then it's probably worth it. The only advantage to the 91' 2500 is the introduction of the 4L80 tranny. I'm not familiar with the typical tranny mated to the diesel on, but if it's already in the 89' that's a great bonus.

Be sure to price a paint job if needed and figure that into the equation. A good paint job can be $3k-$5k I'm guessing......

I'd drive it and see how it performs. Worth a shot!

The person who has the suburban said that it did have a turbo 400 transmission but he took it out and got a 4l80 transmission rebuilt(he has reciept of it too) and installed.

And as for paint. A good buddy of mine has a paint and body shop and he gave a me a decent price on the paint

 

[jeff in co]

I was just in New Orleans a few months ago.....so.....how is the AC system working for both trucks? That can get very expensive quickly! And I assume a must for you....

 

[blackandgold51]

I was just in New Orleans a few months ago.....so.....how is the AC system working for both trucks? That can get very expensive quickly! And I assume a must for you....

The ac in my 90 1500 blows air but needs to be recharged. While the 89 2500 needs a plug to a clutch fan or some short. Overall however I don't use the ac like talking about it. I just have the Windows rolled down.

 

[campfire]

If you are wanting a 6.2 truck, I would jump on this one. The 4L80 (verify that this truck actually has one) is a good transmission with a reputation for longevity and sturdiness. As they didn't come out until 1991, they are quite rare in square bodied trucks, so it's a real bonus when you find one (freshly rebuilt, no less!). The late model 6.2 will also have a serpentine belt instead of V-belts. If you do light towing and don't drive like a maniac, you will probably be one of the folks who really likes the 6.2 engine. Like me. Even for heavy towing, the 6.2 is a good workhorse engine by 1985 standards.

If it came from the factory with typical 3/4-ton towing gears, and he added O/D without adjusting the gears, you will probably be pretty happy on the road (6.2 engines like spinning slowly). I can expound on the technical details of gear ratio selection if you're concerned.

Like any truck, mileage can vary quite a bit depending on gearing and configuration. You might get 25MPG, or you might get 17MPG (likely somewhere in the middle). But you will probably beat the mileage of your old Suburban.

If it's really in such excellent condition, and you want a 6.2 badly enough to consider an engine swap, I don't see any reason to *not* jump on this one.

 

[blackandgold51]

If you are wanting a 6.2 truck, I would jump on this one. The 4L80 (verify that this truck actually has one) is a good transmission with a reputation for longevity and sturdiness. As they didn't come out until 1991, they are quite rare in square bodied trucks, so it's a real bonus when you find one (freshly rebuilt, no less!). The late model 6.2 will also have a serpentine belt instead of V-belts. If you do light towing and don't drive like a maniac, you will probably be one of the folks who really likes the 6.2 engine. Like me. Even for heavy towing, the 6.2 is a good workhorse engine by 1985 standards.

If it came from the factory with typical 3/4-ton towing gears, and he added O/D without adjusting the gears, you will probably be pretty happy on the road (6.2 engines like spinning slowly). I can expound on the technical details of gear ratio selection if you're concerned.

Like any truck, mileage can vary quite a bit depending on gearing and configuration. You might get 25MPG, or you might get 17MPG (likely somewhere in the middle). But you will probably beat the mileage of your old Suburban.

If it's really in such excellent condition, and you want a 6.2 badly enough to consider an engine swap, I don't see any reason to *not* jump on this one.

I forgot to mention that the one who is selling the 89 3/4 ton said that he's in no rush to sell to anyone nor hurting for cash. He said he has other cars . along with a trailer/mobile home and he's trying to make room. He even said he rather sell it to me than anyone else. He turn down some people along with the fact that they don't know much about diesels(guy who is selling the su urban has been a truck driver for over 30 years)


Also if you want pictures I can show then to you.

 

[blackandgold51]

If you are wanting a 6.2 truck, I would jump on this one. The 4L80 (verify that this truck actually has one) is a good transmission with a reputation for longevity and sturdiness. As they didn't come out until 1991, they are quite rare in square bodied trucks, so it's a real bonus when you find one (freshly rebuilt, no less!). The late model 6.2 will also have a serpentine belt instead of V-belts. If you do light towing and don't drive like a maniac, you will probably be one of the folks who really likes the 6.2 engine. Like me. Even for heavy towing, the 6.2 is a good workhorse engine by 1985 standards.

If it came from the factory with typical 3/4-ton towing gears, and he added O/D without adjusting the gears, you will probably be pretty happy on the road (6.2 engines like spinning slowly). I can expound on the technical details of gear ratio selection if you're concerned.

Like any truck, mileage can vary quite a bit depending on gearing and configuration. You might get 25MPG, or you might get 17MPG (likely somewhere in the middle). But you will probably beat the mileage of your old Suburban.

If it's really in such excellent condition, and you want a 6.2 badly enough to consider an engine swap, I don't see any reason to *not* jump on this one.

If you can, tell me the technical details

 

[blackandgold51]

If you are wanting a 6.2 truck, I would jump on this one. The 4L80 (verify that this truck actually has one) is a good transmission with a reputation for longevity and sturdiness. As they didn't come out until 1991, they are quite rare in square bodied trucks, so it's a real bonus when you find one (freshly rebuilt, no less!). The late model 6.2 will also have a serpentine belt instead of V-belts. If you do light towing and don't drive like a maniac, you will probably be one of the folks who really likes the 6.2 engine. Like me. Even for heavy towing, the 6.2 is a good workhorse engine by 1985 standards.

If it came from the factory with typical 3/4-ton towing gears, and he added O/D without adjusting the gears, you will probably be pretty happy on the road (6.2 engines like spinning slowly). I can expound on the technical details of gear ratio selection if you're concerned.

Like any truck, mileage can vary quite a bit depending on gearing and configuration. You might get 25MPG, or you might get 17MPG (likely somewhere in the middle). But you will probably beat the mileage of your old Suburban.

If it's really in such excellent condition, and you want a 6.2 badly enough to consider an engine swap, I don't see any reason to *not* jump on this one.

For overdrive , he did say that is has "3 speed with overdrive". "With the two d's in the gear selector box"

 

[campfire]

I forgot to mention that the one who is selling the 89 3/4 ton said that he's in no rush to sell to anyone nor hurting for cash. He said he has other cars . along with a trailer/mobile home and he's trying to make room. He even said he rather sell it to me than anyone else. He turn down some people along with the fact that they don't know much about diesels(guy who is selling the su urban has been a truck driver for over 30 years)


Also if you want pictures I can show then to you.

Pictures are always good.

 

[campfire]

For overdrive , he did say that is has "3 speed with overdrive". "With the two d's in the gear selector box"

The gear selector box labeling does not have much relevance if the tranny has been swapped. a 4l80 tranny will have 4 speeds total (counting O/D).

 

[campfire]

If you can, tell me the technical details

About what? The gearing options? Your engine has a particular RPM range where it is good at generating power efficiently. When loaded down, you want to do your highway cruising inside this range. If you're lightly loaded (using less power), spinning the engine more slowly will increase mechanical efficiency even more. Gasoline engines operate most efficiently when spinning slowly with the throttle wide open (generating exactly the amount of power needed without wasting any capacity). Nobody drives quite like that, but getting closer to that end of the spectrum will provide better efficiency than if you were spinning faster at 10% throttle. Diesel engine efficiencies are more complicated, as they get less efficient (thermally) under heavy throttle loading, but they still lose mechanical efficiency when spinning more quickly. So you wind up with a balancing act.

Basically, for both engine types, gearing for power will cost you efficiency-wise. 3/4-ton trucks are typically geared for towing, and often overgeared for highway cruising & light trailering. If the owner of this Suburban added O/D to a truck that was geared for a non-O/D transmission, the truck will be more gutless on the highway now than it was before. But it should also pull better mileage. If you're not towing heavy loads or running large mud tires, you will probably be happy with the trade off. If not, simply shift down to 3rd and you'll be back to factory gearing.

I've been guessing that this truck is geared for towing. But rather than guessing, why don't you find out what gear ratio & tire size the truck has? Then we can have a more informed conversation about the pros and cons of your particular combination.

 

[blackandgold51]

Pictures are always good.

I'll show you my 90 1500 4x4 in a little bit.....

 

[campfire]

You check the VIN on that truck yet? I would not expect to see 6-lug wheels if that is truly a 3/4-ton.

Pictures of transmission pan (to verify it's a 4L80), engine compartment, rear axle cover, etc. would help establish the condition of the mechanical side of things.

 

[blackandgold51]

You check the VIN on that truck yet? I would not expect to see 6-lug wheels if that is truly a 3/4-ton.

Pictures of transmission pan (to verify it's a 4L80), engine compartment, rear axle cover, etc. would help establish the condition of the mechanical side of things.

I'll take pictures of it and send it to you soon

 

[blackandgold51]

You check the VIN on that truck yet? I would not expect to see 6-lug wheels if that is truly a 3/4-ton.

Pictures of transmission pan (to verify it's a 4L80), engine compartment, rear axle cover, etc. would help establish the condition of the mechanical side of things.

The 6 lug pattern was another combination for the 2500s besides just 8 lugs(basically a different option); http://www.discountedwheelwarehouse.com/Chevrolet_2__Vehicle_Bolt_Pattern_Reference.cfm

https://www.gmheritagecenter.com/do...ion-kits/Suburban/1989-Chevrolet-Suburban.pdf

 

[campfire]

@82355 : Martin, does this ring any bells? I was thinking that the 6-lug 3/4-ton wheels didn't start until the GMT-400 years.

FWIW, I didn't see the reference to 6-lug wheels in that options brochure. You'll have to point it out to me.

I will again suggest you check the VIN, just to see what the truck started out as. It's a bit on the strange side for a 3/4-ton. It's trimmed out very nicely, it has 6-lug wheels, and O/D shifting indicators shouldn't have been available for 3/4-ton Suburbans. Plus, you have already been told that it has been through some modifications (a pretty labor-intensive transmission upgrade, to say the least). So you have a bit of an oddball truck here. IMO, it's worth checking the things that you can check before you decide to buy it. Check the VIN. Check the weight rating on the door tag. Check to see which rear axle you have. Check to see that it's actually a 4L80E. Assuming that it is, what sort of computer is running it, and where is it getting its VSS signal from ('89 would have been mechanical speedometer originally)? Has the speedometer been converted to VSS to match the tranmission? Why does the quarter panel not match? Has this truck been crunched at that corner? Lots of questions come up when I think about it.


I still think it's worth jumping on if it all pans out. But the time for asking questions is now.

 

[jeff in co]

I'm almost thinking it's a 1/2 suburban with a newer driver's side door that says 2500 on the side. The blue paint looks more shiny than the back half of the truck and the front fender has obviously been changed out. Maybe driver's door got changed too and was lucky to find same color combo. What does the front passenger door say?

From the two links, I would go by the gm heritage one. I don't see in there any 2500's that have 6 lug. What page are you looking at?

 

[campfire]

I'm almost thinking it's a 1/2 suburban with a newer driver's side door that says 2500 on the side. The blue paint looks more shiny than the back half of the truck and the front fender has obviously been changed out. Maybe driver's door got changed too and was lucky to find same color combo. What does the front passenger door say?

From the two links, I would go by the gm heritage one. I don't see in there any 2500's that have 6 lug. What page are you looking at?

I had the same thought. The driver door doesn't seem to match, and so many other things are screaming HALF TON. That may or may not matter to the O.P., but it's worth finding out now vs. later.

 

[blackandgold51]

I had the same thought. The driver door doesn't seem to match, and so many other things are screaming HALF TON. That may or may not matter to the O.P., but it's worth finding out now vs. later.

You're right..... it does say halfton . somethin tells me it does