Answer My Peeve

[vtblazer]

Why do people build trucks with big tires and 1/2 ton axles/running gear?

I'm relating to 37" and up sized tires on 6-lug half ton axles.

Besides the fact that breakage is imminent at some point, I see it as a major safety issue based on physical braking surface size and basic brake design.
Then it continues on with steering, shock and large unsuspended weight issues.
Seems crazy dangerous to me in so many ways.

Maybe I'm thinking to much into it but I just can't understand it.

[-Greg72]

Ignorance.

[mothertrucker424]

well mine is 1/2 ton and i understand its limits i don't tail gate and ease to a stop andone day i'll opt for 1 ton axles and the shbang but now this is what i can afford

[vtblazer]

Originally Posted by mothertrucker424

well mine is 1/2 ton and i understand its limits i don't tail gate and ease to a stop andone day i'll opt for 1 ton axles and the shbang but now this is what i can afford

With 33's your not in the 'danger zone' but simply knowing and driving accordingly makes a big difference.

[shelby987]

I would say it all comes down the $$$.....I am looking at doing the upgrades, and unfortunately, suspension, wheels, tires, and axles all to put the truck up in the air on some nice tires and keep the gear at a safe level gets expensive quick......I am luck with the 3/4t....but I still don't want much larger than my soon to be 34" without king pins! (I am just happy I can keep the same wheels when it is all said and done).....I haven't found an easy way to do it in stages just yet (aside from buying parts in stages....and leaving them in the garage).

[Burt4x4]

Pavement Pounders & Rookies
Bought Not Built
Silver Spoon City Slickers

That should help you understand why you see that done

[Yukon Jack]

This will be a laugh for you - as you may recall I did the reverse, I upgraded to 3/4 ton gear on my 70 K5 so I could run these bad boys



Sweet tread but IIRC they are only like 31". When I got the K5 its tires were shot and the cheap chrome rims were in bad shape also. I had the above tires with excellent tread - these tires and rims were left over from when I lifted my 69 K20 initially and put on the 35"s. The K5's axles needed brakes and it was drums all around so my smart brain said, get 3/4 ton axles to gain disk brakes up front and the mighty 14 bolt FF out back and then I can use these tires on their existing 8 lug rims. Made alot more sense money wise to me.

For the guys running 37" or larger tires on 1/2 gear, I think it comes down to a $$$ issue and a bit of ego - it's cool to have big tires and you can have big tires for $1,300 to $1,500 on your existing 6 lug rims or do it right for an extra $500 for 8 lug rims and $1,000 to $1,500 for 1 ton axles. It's easy to forget the safety aspect when you going for the look and don't have the extra $2,000 or so to move up to 8 lug rims and 1 ton axles.

I also think alot of people forget the very thing that worries you most - those big tires weigh a lot and compromise the 1/2 ton gear's ability to safely stop due to that extra weight. I think alot of people focus on the worry of breaking the axle with the big tires and think in their mind, I'll just drive it easy, but I see the bigger concern that you do - the ability of the axle to control that much tire. In an emergency situation, can the 1/2 ton gear stop a 37" tire as well as a 31" tire, of course not.

Whenever I see a post about someone considering going with big tires with 1/2 axles, I always try to mention the braking/safety issue - maybe it falls on deaf ears, but if we all point it out to them, maybe we can shift the focus from "you're axles won't hold up to those tires" to "your axles can't safely stop those tires and you might end up killing someone."

[Zoomad75]

I agree on some points made here. Some guys put the cart in front of the horse and get the big tires first and then save up for the upgraded running gear later. Others just do it to have big tires. (poser)

I have to say my K5 is maxed out on tire size at 35" with my current 1/2 ton axles. Even when I do get a 14bolt I'm most likely just going to add the 8 lug parts to my existing D44. Why not a D60? Because money don't grow on trees around here. With an open D44 and 35's and light right foot the front axle will live a long life under my K5. The 8lug parts will give a larger rotor for more swept area, greater heat dissapation. The big drums out back on a 14 bolt are almost twice the size of the 12 bolt stuff.

I my case I fit into the first category. I needed tires and rather than buying a larger set later I bought the size I wanted. I know the limits of the stock 1/2 ton axles and try not to beat on them. It means I take the hook sooner, but my truck ends up driving home after we get off the trail.

Now a old Nieghbor of mine back in the burbs of Detroit built a total poser mobile. 1988 NBS, 1/2 ton with 6" of lift and 38" tires on a stock 10b rear and IFS up front. I teased him all the time he's going to break a 10bolt shaft on the way to the gas station. He really didn't get it for a long time. But since he had so much money wrapped up in nice aluminum rims he didn't want to have to change to 8 lug parts. He at least found a 6 lug 14 bolt semi floater axle for the rear and was going to stuff a 3/4 ton diff up front while keeping the 6 lug outers. Still a poser to me but he does wheel it at the silver lake dunes from time to time.

Unfortunately you cant convince them all. It usually takes a broken axle for somebody to wake up and see the light.

[shilo]

I didnt think there was a difference between 1/2 and 3/4 brakes on a dana 44. How much of a difference is there?

[Yukon Jack]

Originally Posted by shilo

I didnt think there was a difference between 1/2 and 3/4 brakes on a dana 44. How much of a difference is there?

For me the benefit of the 3/4 ton Dana 44 for my K5 was I went from the 1/2 ton Dana 44 with drum brakes to the newer 3/4 ton Dana 44 with disks. I don't know if a disk braked 1/2 ton Dana 44 is different than a disk braked 3/4 ton Dana 44 - I'm guessing they are the same.

If you're stepping up from a 1/2 ton setup to accomodate tires in the 37" or larger size I wouldn't be recommending going to the 3/4 ton Dana 44, I'd be recommending the Dana 60 for strength as well as better braking.

[vtblazer]

Originally Posted by Yukon Jack

For me the benefit of the 3/4 ton Dana 44 for my K5 was I went from the 1/2 ton Dana 44 with drum brakes to the newer 3/4 ton Dana 44 with disks. I don't know if a disk braked 1/2 ton Dana 44 is different than a disk braked 3/4 ton Dana 44 - I'm guessing they are the same.

Even so, the master cylinders are different, correct?
Maybe that's how they achieve the better braking power in the 3/4 ton set up.

[Yukon Jack]

I don't know if the master cylinders are different between the 1/2 ton and 3/4 ton. I swapped the 3/4 ton donor truck's master cylinder in when I swapped in the 3/4 ton Dana 44 as my K5 had manual brakes and the donor truck had power brakes.

[68,69 K20]

I believe it may be ignorance on some peoples part, I know too many people who think that 4x4= unbreakable. Several years back one of my buds put 36' or 37's on his mid 80's half ton, no other drivetrain mods were made, and he couldn't understand why it wouldn't stop or steer...he finally got the point when the rearend grenaded and shot the pass side axle over about a 15 ft embankment and the truck was close to following....Some just dont get it!!!

[vtblazer]

Originally Posted by Yukon Jack

I don't know if the master cylinders are different between the 1/2 ton and 3/4 ton. I swapped the 3/4 ton donor truck's master cylinder in when I swapped in the 3/4 ton Dana 44 as my K5 had manual brakes and the donor truck had power brakes.

Not positive with other years but yeah, our years have different masters/boosters.

That's one of the best mods you can do to make the sorry-a$$ half ton brakes work better, switch in a 3/4 or 1 ton set up and presto, better brakes.

[Yukon Jack]

You're right about that! I went from manual brakes on my 69 K20 to hydroboost from a 1 ton and the difference was astonishing - and that is with drum brakes all around! I can't wait until I swap out the drum brake front axle for the Dana 60 shortly - I will probably knock my head agaisnt the windshield the first time I hit the brakes

[jeffspower]

Im not sure what years/ GVW's had what- but some of the 3/4 ton front axles had calipers with bigger pistons than the 1/2 tons. I found this out when I went to put a '81 1/2 ton caliper on an '80 3/4 ton. The banjo bolt for the brake hose was bigger too.

[bad_turbo]

My "67 1/2 ton suburban got a new master cylinder (for a 1/2 ton) then 2 months later I swapped in 3/4 ton front and rear axles, along with the suspension, off of a '68 GMC truck so I could run 37 inch tires. No problem with the brakes at all.

[wibilly]

Why do people build trucks with big tires and 1/2 ton axles/running gear?

in my opinion they arn't built trucks they are jacked up pos that are worthless for trucks or wheelers unsafe on or offroad

[ND_guy]

1/2ton D44 Rotor Diameter 11.875"
3/4ton D44 Rotor Diameter 12.480"
D60 Rotor Diameter 12.870"

I was going to upgrade my pickup after it ate two lockouts this year. Now, I don't have to since I nuetered my pickup, by pulling the 400 out.

[eric67m]

Thats it, I am going to do the complete opposite.

How about going with 2 1/2 ton Rockwells and then finding a way to adapt them down to the smallest wheel and tire possible. (Think 13" Dayton wire spokes with low profile white walls (90's lowered cars))

[ND_guy]

Eric I love it, but I dont think 100 spoke Daytons could support the weight of a Rockwell! On second thought, the center diff would be on the ground so they wouldn't have to support the axles. GO FOR IT!

[earl87gta]

I think the big problem is all the mags these guys read are always talking abought jeeps well if you put 37in tires on a jeep with a d44 then ya no trouble but on a full size truck that waighs 2 to 3 times as much its a hole new battle the mags seem not to talk about that. Im with what Yukon most of these guys are thinking how to keep from breaking an axle and not how will this afect my stopping power. All we can do is voice our opinons on line and hope that our advice will over ride wht they think the mags are telling them is ok.

[vtblazer]

Okay, so the concensus is all about the same.

So everytime I see another one, I'll just shake my head and think 'TARDS' quietly to myself.

[shilo]

i run narrowed 1 ton in my jeep with a stock wrangler master cylander and vaccum booster. My jeep came with manual brakes, but now i can lock up the 39.5 boggers anytime.

[Dean]

Reminds me of my first 4x4 in high school. 78 K10 shortbed with 38" gumbo mudders. Lack of funds was the issue....lol. I drove it around most of the time in low range too.

It was fun though helping the cheerleaders get up in my truck......lol