Is my gearing all wrong?

[kmamf]

My set-up is a stock 92 Chevy 350, TH-350 tranny, NP-203, 5.13 gears, 44" TSL's. I just took this rig on it's first real outing. I just had the tranny rebuilt last Monday. I ran trails (in low lock) 1/2 day Friday and all day Saturday in Clayton, OK. I ran trails rated 4, 5, and 6 ( didn't hammer the rig either). On the 2nd trail on Sunday, the tranny started slipping. Luckily I made it to pavement before I lost all forward gears. Would you say my gearing is too tall and that's what caused the tranny to go or would you say it was a half-assed rebuild job? I can't afford a doubler at this time but I can't afford a tranny rebuild every outing. Thanks for the input.

[95steel]

Well, I'd say a doubler would help. Sounds like a good set up for wheel speed, not for crawling.

I bet your tranny was getting HOT lugging that hard. How big is your tranny cooler? Did you burn fluid, or trash internal parts? Are you running a stock converter?

[Odin K30]

I agree with 95steel.
Sounds like you overheated and killed your TH350 what size trans cooler and converter are you running?
If youre just running the internal radiator cooler...theres your problem.

[kmamf]

Im using a stock converter. The cooler is a double cooler (12" x 12")- it has a 4-pass for the hydro assist steering, 2-pass for the transmission, with an electric fan (Hayden 19511) mounted on it. The cooler is mounted about about 3" off of the side panel behind the driver's seat with the fan. The fluid is pretty dark so it's burnt. Looks like I need a bigger cooler, a trans temp gauge, a new tranny, and smaller tires. Sound about right?

[Blind Driver]

Originally Posted by kmamf

Im using a stock converter. The cooler is a double cooler (12" x 12")- it has a 4-pass for the hydro assist steering, 2-pass for the transmission, with an electric fan (Hayden 19511) mounted on it. The cooler is mounted about about 3" off of the side panel behind the driver's seat with the fan. The fluid is pretty dark so it's burnt. Looks like I need a bigger cooler, a trans temp gauge, a new tranny, and smaller tires. Sound about right?

New trans and a bigger cooler with a fan. I'd go with a Turbo 400.

Maybe lower the stahl speed of the converter?

[mopar redneck]

I'm surprised. I used to run 39's, stock, worn out small block, and 3.90's and lockers and never burnt the tranny up.

[kmamf]

I was surprised, too. I would understand if I was hammering on it hard but 2 days of wheeling shouldn't have killed it in my opinion. My last rig near this size was a CJ with an auto, D300, 4.88's and 38.5's and a tiny cooler mounted on the front of the radiator with no fan. The tranny held up in it.

[Warpig58]

I wouldn't discount the possibility the rebuilder messed up and that's why it died so fast. A temp gage on the trans output line will let you know when things are getting to hairy.

[77k5]

I would blame the rebuild.

If you don't have a trans temp gauge get one as soon as possible.

[old ugly 54 chevy]

with it in low-low it's a 25.98 to 1 final gear ratio,should not of built too much heat,did you flush your cooler and lines before you installed the new tranny?Did you inform the rebuilder what you planned on doing with it?Tranny shops around here will take a little more time on one if they know its going to be worked a little harder.

[kmamf]

I did not flush the cooler and lines before installing the new tranny. Yes, the rebuilder knew what I was doing and tried selling me a TH400 converter to go on it saying it would give me a lower stall. I went and told him yesterday that the tranny lasted 2 days...his response was maybe he broke a ring when he reassembled it...he would just have to rebuild it again. I'm done with him. I've found a used one for $200. I'll put it in, install at least a 4 pass mondo cooler with it's own fan, and a temp gauge. I saw on ebay where I can order a rebuild DVD and the kits to rebuild the tranny, so I'll learn how to build my own tranny and start on the one I take out. The rebuild kit, DVD, and other used tranny will still cost me less than having someone rebuild one for me.

[bigfkr]

Your rebuild didn't come with a warranty? Any GOOD tranny shop will give a warranty with their work.

This doesn't always work out though. I had a pro-built th400 go bad 3 times in 5 months once. The guy kept blaming the parts he put in (all top of the line stuff, redline clutches, 34 element sprag etc.) so I had to keep paying for rebuilds. Finally I went somewhere else and had no problems....

I would have him warranty it, but definatly get more cooling....

[Blind Driver]

Originally Posted by kmamf

I did not flush the cooler and lines before installing the new tranny. Yes, the rebuilder knew what I was doing and tried selling me a TH400 converter to go on it saying it would give me a lower stall. I went and told him yesterday that the tranny lasted 2 days...his response was maybe he broke a ring when he reassembled it...he would just have to rebuild it again. I'm done with him. I've found a used one for $200. I'll put it in, install at least a 4 pass mondo cooler with it's own fan, and a temp gauge. I saw on ebay where I can order a rebuild DVD and the kits to rebuild the tranny, so I'll learn how to build my own tranny and start on the one I take out. The rebuild kit, DVD, and other used tranny will still cost me less than having someone rebuild one for me.

He admitted fault? Let him rebuild it.

[lumpdog]

The t350 is plenty of transmission for ya. Making sure it is staying cool is key to the trans life.

I run a 700/205 with 4.56 gears and 44's, but I do stupid stuff like that since I build transmissions, I call it durability testing. Point is that my trans has lasted for years, and I overheat the pee out of it quite a bit.

I would definitely get the junkyard one. Then, sit down in your garage with a good th350 build manual, pay attention to detail, and build one yourself. It is really hard to mess up a th350.