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3/4 ton conversion?

This is a discussion on 3/4 ton conversion? within the Tow/Haul Mode forums, part of the General Discussion category; I have a 1989 1/2 ton, normally i'm hauling car haulers around a couple times a week, the 350 has ...

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    3/4 ton conversion?


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    I have a 1989 1/2 ton, normally i'm hauling car haulers around a couple times a week, the 350 has no problems with it and the 700r4 does ok if you keep in in D, my problem is the suspension, it gets sacked out quite easily with even a small car on the back, i was thinking of adding a leaf, or even just bolting in leafs from a 3/4 ton.. can this be done? any suggestions?

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    Re: 3/4 ton conversion?

    I'm towing a Jayco 32 BHDS (36'5" long) with my '99 1500 ECSB 4x4. I swapped the rear springs for a set off a 2500HD. It helped, but by no means did it (or did I expect it to make) the truck a 3/4 ton. It helped some with the sway, that being said, as soon as money allows, I will be upgrading to a 3500 SRW. As far as the swap, it was a fairly easy swap. Just had to cut the front left bolt off because of the way GM put it in had they put it in the other way, it would have come out w/o cutting. Then I had to have longer u-bolts made by a local spring company. I wouldn't think a OBS would be any different.

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    Re: 3/4 ton conversion?

    Thanks for the quick reply, looks like ill have to take a trip to the wrecker

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    Re: 3/4 ton conversion?

    I will completely agree with what he said.
    Nothing you can do to that truck will make it a 3/4 ton. You can put 3/4 ton springs in it, but you really need a 3/4 ton truck.


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    Re: 3/4 ton conversion?

    Air bags and/or 3/4 springs will bring the rear ride height up during hauling or towing, however the safest (read:smartest) thing to follow that up with is a 3/4 or 1 ton braking system.
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    Re: 3/4 ton conversion?

    Trying to upgrade a 1/2ton to a 3/4 is not safe or smart period.
    Upgrading a 1/2 ton to carry an acceptable weight is.
    Upgrading springs, brakes, sway bars, engine power, trans cooling, trans strength will make it seem like it can handle the same as a 3/4 ton.
    However it will still be a 1/2 ton with 1/2 ton axles (yes you can swap in a 14 sf or ff) but even then you still have a 1/2 ton frame.
    No matter what you do you cannot safely or smartly upgrade to a heavier truck without buying that heavier truck. Period.
    Having said that I will restate that you can upgrade your current truck to make it pull/handle/stop better. This is a great thing for the weights a 1/2 ton should have, same deal for 3/4 and 1 ton.


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    Re: 3/4 ton conversion?

    gm makes what they call a "heavy half", look it up. its a half ton obs truck with 3/4 ton 14 bolt sf rear axle and springs with six lug rotors for the front. its is perfectly safe and can be considered a OEM swap, at least its a factory option.

    to say you can not upgrade, shows what you know...

    keep an eye on my signature as i will be upgrading my work truck soon.
    Last edited by nine5yukon; 06-09-2011 at 03:53 PM.

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    Re: 3/4 ton conversion?

    People call it that but it's just a 1500 with heavy duty suspension; the front brakes which are the majority of your stopping power are the EXACT SAME SIZE as 1500 brakes just 6 lug instead of 5 lug. The rear brakes are larger due to running the 14 bolt rear end but that's it. A 1500 with HD suspension, or a 2500LD, are just barely more capable than a 1500...not to be confused with a regular 2500 truck. The difference is so minimal there's no reason to go through the work/expense of "upgrading" - if you think it's a significant improvement other than the strength of the 14 bolt compared to 10 bolt, you're kidding yourself.

    FYI my daily is a 2500LD.

    Richard

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    Re: 3/4 ton conversion?

    Quote Originally Posted by someotherguy View Post
    People call it that but it's just a 1500 with heavy duty suspension; the front brakes which are the majority of your stopping power are the EXACT SAME SIZE as 1500 brakes just 6 lug instead of 5 lug. The rear brakes are larger due to running the 14 bolt rear end but that's it. A 1500 with HD suspension, or a 2500LD, are just barely more capable than a 1500...not to be confused with a regular 2500 truck. The difference is so minimal there's no reason to go through the work/expense of "upgrading" - if you think it's a significant improvement other than the strength of the 14 bolt compared to 10 bolt, you're kidding yourself.

    FYI my daily is a 2500LD.

    Richard
    ^what he said. No point in me being a parrot.

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    Re: 3/4 ton conversion?

    nine5yukon
    I never said you cannot upgrade, matter of fact if you actually read my post I stated it can be a good idea. But trying to upgrade a 1/2 ton to a 3/4 ton cannot be done and is completely unsafe.
    The only "upgraded" 1/2 ton I would actually use is a 3/4 ton with a 1/2 ton body.
    Other then that 14bt sf or ff you still have a 1/2 ton frame.
    So no you still cannot upgrade to a 3/4 ton without buying a 3/4 ton.


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    Re: 3/4 ton conversion?

    it seems a common misconception that ALL hd chassis 1500 had 14bolt and 6lugs which is not the case. my 2wd 89 had the hd chassis and had a 10 bolt , 5lug wheels, hd springs, wider rotors, bigger spindles and bearings. it would be a guess but maybe the difference is earlier vs later obs or 4wd but i dont know that i just know what i had.

    to the op if you can find rear springs for a truck like i had, it hauled 6000 camper just fine with a 350 and 5spd
    Last edited by ToyHauler; 06-12-2011 at 11:48 AM.
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    Re: 3/4 ton conversion?

    Quote Originally Posted by 89red View Post
    I have a 1989 1/2 ton, normally i'm hauling car haulers around a couple times a week, the 350 has no problems with it and the 700r4 does ok if you keep in in D, my problem is the suspension, it gets sacked out quite easily with even a small car on the back, i was thinking of adding a leaf, or even just bolting in leafs from a 3/4 ton.. can this be done? any suggestions?
    What kind of weight are we talking?

    Are we within the limits of the 1/2 ton truck's capacity, just that you want it to sag less? In that case, throw in some air bags, an add-a-leaf, or a new spring pack.

    Are you towing too much with it and trying to beef the truck up to handle it? Time to buy a new truck....


    Like kcb37 has been saying, you can't really upgrade from a 1/2 ton to a 3/4 ton with just component swaps. Frame, brakes, rear axle, bearings, transmission, often oil cooler & radiator, etc etc is all beefier on the heavier trucks. My 92 C2500 weighs more than my 92 K1500 work truck did, despite one being 4wd.....(both regular cab long beds, tow package, etc)

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    Re: 3/4 ton conversion?

    Quote Originally Posted by ToyHauler View Post
    it seems a common misconception that ALL hd chassis 1500 had 14bolt and 6lugs which is not the case. my 2wd 89 had the hd chassis and had a 10 bolt , 5lug wheels, hd springs, wider rotors, bigger spindles and bearings. it would be a guess but maybe the difference is earlier vs later obs or 4wd but i dont know that i just know what i had.
    No misconception, just no point in describing every possible variation when the real point is, he's not going to make a real 3/4 ton out of a 1/2 ton.

    It is correct that a 2WD 1500, 1500 w/HD package, or a 2500LD would be 5 lug...and would be 6 lug if it's 4WD. Then again the 4WD would be 6 lug whether it were a plain 1500, 1500 with HD package, or 2500LD anyway.

    Richard

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    Re: 3/4 ton conversion?

    Last 2500LD I saw in the JY was 6 lug, not a 5. On an OBS, if you're willing to do the 8 lug swap, hydroboost, 4L80E, fluid coolers, etc there's no reason why it can't be a 3/4 ton. It's not like NBS and newer where the HD's have a completely different frame. The only frame difference that I'm aware of on the OBS's are that the UCR mounting ears are taller on HD's and the front diff mounts are different. People say they're thicker, but they're not. I've seen a zillion 3500's in the JY whose frames were the exact same thickness as my half ton. A lot on here will disagree, but if you're not exceeding the weight limit any of bearings, brakes, springs, and your truck aptly handles its load, I see no danger. *dons flame suit*
    Last edited by speedracer326; 06-16-2011 at 11:24 AM.
    Quote Originally Posted by Quyonmob View Post
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    Re: 3/4 ton conversion?

    Quote Originally Posted by speedracer326 View Post
    Last 2500HD I saw in the JY was 6 lug. On an OBS, if you're willing to do the 8 lug swap, hydroboost, 4L80E, fluid coolers, etc there's no reason why it can't be a 3/4 ton. It's not like NBS and newer where the HD's have a completely different frame. The only frame difference that I'm aware of on the OBS's are that the UCR mounting ears are taller on HD's and the front diff mounts are different. People say they're thicker, but they're not. I've seen a zillion 3500's in the JY whose frames were the exact same thickness as my half ton. A lot on here will disagree, but if you're not exceeding the weight limit any of bearings, brakes, springs, and your truck aptly handles its load, I see no danger. *dons flame suit*
    If you saw what you think was a "2500HD" and it was 6 lug, I'd have to ask what year it was, and what you consider "HD" - if you mean GMT400, aka "OBS", then there are two flavors of 2500 - 2500 "light duty" which is 7200lb GVWR, 6 lug and essentially a 1500 with a better rear axle and a little extra spring, and there's the 2500 "heavy duty" which is 8 lug, and 8600lb GVWR. They are very different suspension and brake-wise.

    There are extra supports, gussets, etc. in the suspension mounting between the two 2500's. Pretend it's "converted" all you want, you would have to change/add so many things you would be money and work ahead just buying the truck you need instead of hacking it together and still coming out with less.

    Richard

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    Re: 3/4 ton conversion?

    Calm down there turbo, I meant LD. I'm quite aware of the different GVWR's. So where are the extra supports, gussets, etc? I've asked this before but nobody ever says exactly what they are or show pics. I mentioned the 8 lug above, as that would include said larger brakes, but I left out the fact that it isn't worth it in the end. Now if he's seeking that 7200# GVWR all he needs is to make sure, since his is an '89, that he gets the larger front brakes found on the extended cabs if his is not, get the 14BSF and leaf pack from an LD2500 and he done assuming brake master cylinders and prop valves are the same. IIRC the 1/2, 3/4, and 1 ton ratings are a letter in the VIN and you can't get a modified door sticker from GM, but the truck would be equipped as GM saw fit to label as 7200# GVWR truck. That's enough for most and would definitely get the OP by. I'd throw some hydroboost in the mix and call it a day unless he's ready to spring for a new truck. The only 3/4 ton I'd ever buy is a DMax ($$$ so not gonna happen) unless I somehow got my hands on the uber rare 2500 XCSB OBS and I can count on 1 hand how many 8 luggers of those I've seen in my life. Even empty the 1/2 ton brakes suck, so hydroboost should be at the top of the list even to stay under the 10,700# GCWR published by Chevy. Has anyone ever noticed that Chevy's OBS trailer tow ratings are base off of pulling power alone? My owner's manual rates the 2WD with 5.7 to pull more than the heavier 1 ton with a 5.7. Just thought I'd muddy the waters a little.
    Last edited by speedracer326; 06-16-2011 at 11:30 AM.
    Quote Originally Posted by Quyonmob View Post
    Straight pipes are for peckerheads. . .
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    Re: 3/4 ton conversion?

    I took a pile of pics and measurements of different model frames when I had my salvage yard, but honestly, doesn't matter if I ever posted them - people will do things like say "Last 2500HD I saw in the JY was 6 lug" then get mad when I correct them. Bad info perpetuates on the 'net as easily as good info, so who cares.

    I'll say it again, my daily is a 2500LD. In no way do I think it's nearly as capable as a regular 2500, and wouldn't consider that upgrading a 1500 to 2500LD parts is a significant advantage and absolutely not in the same class as a regular 2500. BUY THE TRUCK YOU NEED, and improve upon that if necessary, but trying to hack a much lighter duty truck into something stronger is a losing proposition.

    Richard
    Last edited by someotherguy; 06-16-2011 at 11:28 AM.

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    Re: 3/4 ton conversion?

    There's a 1000# difference in GVWR between a 1500 and LD2500 by simply swapping an axle and leaf pack, I consider that a pretty good bang for the buck when you figure bigger brakes out back come with it. If you're only ever going to pull 5-6k on a flatbed car hauler, I just don't see the need for a 3/4 ton if you already own a 1/2 ton. My truck with the 10 bolt setup took a 5k trailer nicely, you could hardly tell it was there. That's why I think a 2500LD is really what the half ton should have been, it's got that extra little bit so now 6k feels like nothing's back there. Isn't that all the OP is trying to pull?
    Quote Originally Posted by Quyonmob View Post
    Straight pipes are for peckerheads. . .
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    Re: 3/4 ton conversion?

    Quote Originally Posted by kcb37 View Post
    nine5yukon
    I never said you cannot upgrade, matter of fact if you actually read my post I stated it can be a good idea. But trying to upgrade a 1/2 ton to a 3/4 ton cannot be done and is completely unsafe.
    The only "upgraded" 1/2 ton I would actually use is a 3/4 ton with a 1/2 ton body.
    Other then that 14bt sf or ff you still have a 1/2 ton frame.
    So no you still cannot upgrade to a 3/4 ton without buying a 3/4 ton.
    You and I tend to agree alot here in the towing section.

    You have appearantly towed heavy a few times in your life. Just dont get why people wont listen to those that have been there. I have towed across the US more times than I want to admit personally.

    There is no safe or legal way to make a 1/2 ton inot a 3/4 ton. C.I.P. A guy a know took a 1/2 ton truck adn put 1 ton suspension under it. Thought that upped his pulling capacity till DOT caught him. Still licensed as a half ton with a half ton frame. Half ton towing capacity.
    Last edited by bowtieguy101; 06-25-2011 at 03:28 PM.
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    Re: 3/4 ton conversion?

    I think there are two schools of thought on this topic, and my original comments might have been misinterpreted. Even if they were not, I want to clearly explain what my thoughts are on this issue.

    1/2 Ton trucks are capable tow rigs, up to their legal weight, however they can definitely improve the efficiency and safety of towing with a few upgrades. The suspension improvements (springs or airbags) will help maintain a level ride height which we can all agree is for safety and stability. The 14SF axle strength itself isn't the goal here, but the improved braking system available. In my opinion, the braking system is the most important upgrade for towing (or even for general driving). Keeping the truck level helps the braking system operate as it was designed and intended to operate.

    I do not suggest these upgrades as a stop-gap measure to substitute a 1/2 ton truck for a true 3/4 or 1-ton truck. I suggest these upgrades as important for any 1/2 ton truck towing or hauling loads appropriate for a 1/2 ton truck. Improved stopping power is always a welcomed upgrade on any platform, in my opinion. If you are doing the work that requires a Heavy Duty truck, then you need to use a Heavy Duty truck.
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