I have a 1980 Chevy 1/2 ton Custom Deluxe with a 4" suspension lift and 38.5x15x15 superswamper boggers...it has a 1976 5.7L with a 4 speed tranny....it was originaly an automatic so it has the higher gears in the axles....i was wondering if anyone had any tips, etc... as to what to do to this truck...i am wanting to run in county fair mud boggs, etc...i also have a very limited budget because I am 17 and just graduated from hight school today 5/29/08...any help would be greatly appreciated...thanks guys  

Get smaller tires (35's) or bigger axles and deeper gears because you are flirting with failure with 38's on those axles. Deeper gears would help even with 35's but at least it will run better with 35 than 38's with current axles and be safer stress wise on axles. It has got to be a bit of a slug now at times in upper gears.  

yea...its a turd...lol...i have a set of 35's for it but i just have the 38's on it at the moment....what would you sugest for suspension or performance or anything like that...thanks for the tire advice by the way  

Go with 35's for a while until you get some coin to replace/upgrade axles and regear them. 35's will give you better clearance too in wheel wheels in any situation. Do make sure your cooling system is 110% because last thing you want is to overheat wheeling off road. Also put fresh fluid (change it) in axles, Tcase and tranny. They all use 80w90 (Unless someone swapped in a NP208) Many fail to do this and it is cheap insurance especailly with a over stressed drive train like you have.  

most of my fluids stay fresh because i have to fill them everytime i run it....i just put a water pump and new radiator in it...and it has an NP205 t-case...that has some major leaking problems..  

Where is a it leaking at?  

the t-case is leaking out of the front and rear seals, and the engine is leaking at the rear main seal. The rear axle is leaking out of the pinion seal. the thermostat is leaking too...because i used a bad gasket...getting fixed tomorrow  

Well none of those seals is expensive or real hard to change and given age it is not uncommon to see this. I would get rear main seal fixed first.  

the engine runs really good but i was thinkin about tearing it down and putting all new gaskets and seals, etc.. in it. Is there anything you would recomend putting in the engine like performance parts wise like cams and what not since i will be running it in the mudboggs ?  

for bogging in the fair grounds the 38.5 are gonna be needed, even if you have 3.73 gears, using low range in the pit will put you through as fast as the guys running 7.33 gears. thats about wheel speed and horsepower. lower gears are needed there, what you have will work in the meantime.

your cam needs to compliment your gearing...  

This is not exactly true here because axle ratio has a big effect one traction. (5.13's will outperform 3.73's in traction any day regardless of tranny and Tcase) 3.73 with 38's is not a good mud bog combo plus it would over power his axles on his limited budget. Best to stick with 35's to be safer with current axles and gears to reduce drive line stress. Nobody even seem to remotely consider drive line and chassis stress that big tires and tall gears create.  

5.13's are gonna be to steep of a gear. the truck is not gonna have enough wheel speed. go to the 35's. if the truck runs fine i wouldn't pull the motor. re-building an engine can turn into an expensive project.