Yet another newbie gear question

[Quaddawg]

Well.... I have found out that my gears are way too high for my tires..

I have a 78 Chev K10, 350/350/203 Dana 44 front 12 bolt rear 36 inch TSL's

I haven't actually counted teeth yet, but with the RPM vs. Speed, I would say they are 3.08's or maybe 3.43's or something. I get about 2000 RPM at 60 mph, and that is ALL it will pull, unless I am going downhill

I was looking up aftermarket gears, and I keep seeing "case change" at 3.73 for both axles.. is this right? Does that mean I can't go to the 4.56's or 4.88's that I need? unless I change the whole axle?


Also, what harm will it do to run around town in low range on the 203?

I do have a part-time kit installed, I did find that out this weekend..


Thanks, great site!!

 

[tRustyK5]

i'd say the easiest way to get deeper gears and a more durable drivetrain is to swap some 3/4 ton diff's under your truck. They commonly come with 4.10's. To regear you'd either need new carriers (locker upgrade at the same time?) or 'thick' gearsets.

4.10's would put you at 2400+ rpm at 60 mph which is still tolerable on the freeway...

For what it would cost to regear your front and rear you could do the swap and not have to worry about the rear again. The front wouldn't be much stronger, but it'd have much better gearing. You would need some 8 lug 15" rims though.

Rene

 

[Quaddawg]

hmmm, you think 4.10 is enough gear for it? I would really like to go at least 4.56..... I was thinking about doing lockers anyway, but that starts to really get expensive.. Reider has a combo with ez-lockers for a pretty good price, but I haven't heard much good about EZ's.... opinions?


I don't mind spending a few bucks, but I don't really want to drop more than a grand or 15 hundred on gears and lockers....

I would feel better about putting in heavier axles, but once again, where do you stop?

4.56's with some sort of locker, I don't mind spending the bucks for that, now, the question is, will it all fit with the stock axles and housing?

More Recommendations??

 

[bigchief427]

gears

cool looking truck!! before i put the 4.88 1 tons under my 81 i was driving around with 39.5 tsls and 3.73's . Now don't get me wrong it was a turd around town but on the highway it would cruise 80-85 without a prob. fourwheeling was strictly a 4lo affair but that was way to too low to drive around town 25-30 mph. it actually was a decent setup for me cause its was awesome on the highway and gave me a good muddin and trail riding range. BUT i didn't have a true low range for steep hills or what not, and i fried my th350 in the process oh well work in progress matt

 

[Quaddawg]

Thanks! I bought it, already built, and needing some things, it needed tires, and I had a buddy that had just bought these 36 TSL's, used them for about a week, and went on up to 38.5's... so he sold them to me for $400.00... I was pretty sure I didn't have enough gear, but the motor was supposed to be strong.. so I couldn't resist putting them on.

I have only had it a few days, and I have been tinkering... I think the timing is retarded, as it isn't pulling the vacuum it should, I am going to mess with it tomorrow, as it is too freaking cold to be messing around outside today... at least under a hood...

It pulls OK in low range, but not great. I have to do something...

Where do I find 8 lug 15 inch wheels?

 

[tRustyK5]

Well, with 4.56's you'll be spinning at 3000 rpm at 65 mph. That pretty much makes any time on the highway miserable.

EZ lockers aren't warranteed for anything over a 31" tire, and they don't usually live long with a tire over 31" from what I've heard. If you plan on wheeling it, and it looks like you do then upgrading to stronger axles is a good place to start. A detroit locker for a 14 bolt FF is about $360, and can be installed by a novice with no special tools.

With a D44 or 10 bolt front I'd personally leave it open with 36's. The wheeling bug hits hard and eventually you'll want bigger tires. This will lead to a D60 front...so no reason to spend anything more than you have to on the front in the interim.

Rene

 

[Quaddawg]

Hmmm, I hear you.

Now I am thinking about just swapping in some 3.73 axles with posi's that a buddy has, for cheap, for now,

and saving up my money for some Dana 60's with 4.56's, and some 38.5's......

instead of spending money on these axles.....


sheesh, so many toys, not enough fundage... this is worse than my ATV's.

lol..


Thanks guys, now I REALLY don't know what I am going to do, I want to keep these 36 TSL's for now, I mean, they are already bought....