Transmission Failure

[freedombro]

I had a rebuilt transmission installed in my '86 345 last August when the slow climb through Utah claimed my original one. On my first long trip since (LA to Sacramento & back) I decided to see a friend in North Fork, CA. Elevation 2500'. After a couple short but steep climbs I started losing power & smoking. Pulled over and realized I was leaking tranny fluid massively. It was 90 degrees outside. I was told it looked like I blew the rear main seal. I can either tow it to Fresno, or try to refill and limp the last MILE (yup, almost made it!) to my destination where I can get help to work on it. The worst part is that the transmission place on Utah installed a tranny cooler available via toggle switch...I forgot to turn it on...DOH! Any thoughts on my best course of action? THX!

[John Woodrow]

Getting the last mile to where it can be fixed will certainly be the best option. Seal replacement is not a big deal. Depending on how severe the leak is you may just want to tow it there. I'd definitely get rid of that switch and install a thermal switch that will engage only when needed. I installed a transmission temperature gauge because I sometimes pull a trailer full of motorcycles and wanted to be able to keep an eye on temperatures. The gauge and installation were pretty painless.

[cwf]

Walk in to twin or call someone to bring you some tranny blood. Let it leak as long as it is merely leaking, not dumping fluid as that can make the road dangerous for other motorists like motorcycles...

[bobmiller1]

What you were told and what may have happened are two different things....if it's smoking it's probably getting on the exhaust...not a good thing,Truro diagnose it before you travel any distance. If necessary have it towed, preferably on a large flatbed because of the tag axle....hope you have good Sam roadside plan otherwise get it. The cooler should be hooked up so you don't have a toggle switch, I don't get that one....never seen a set up like it either. Good luck, Regards, Bob

[Jjona5]

Could have just boiled out. Bad for the transmission but maybe not dead. Let it cool down, add more fluid, and turn on your cooling fan.

[John Woodrow]

If it's only a mile to town, find a kid with a big bad smoker truck and a log chain. Don't make this any more complicated than it gas to be!

[freedombro]

Originally Posted by Jjona5

Could have just boiled out. Bad for the transmission but maybe not dead. Let it cool down, add more fluid, and turn on your cooling fan.

Jjona5 was correct! Brian at Hank's Automotive in North Fork, CA diagnosed the problem over the phone. He explained that my turbo 400 has a vent tube designed to allow overheated transmission fluid to escape. Not good for the tranny, but definitely not the trip killer I was afraid of. After cooling overnight, I replaced the missing fluid and the rig ran and shifted better way than before.

Due to the deep pan on this model, he suggested running the fluid level at the add a pint mark in hot conditions. Besides leaving the cooling fan on, he also suggested swapping out for a brass ALLISON filter and double o-rings on the pickup tube when I get home. Their shop is at the top of a pretty steep grade, so they have a lot of experience with this issue. I made it back to LA with no issues and am very grateful for the free advice from Brian at Hank's.

I was told that Star Tron Enzyme Fuel Treatment helps these older 454s process today's shitty corn-gas. I tried a bottle on my last fill-up and the difference was stunning. I will be running it in all my vehicles from now on. That's my tip for the day.

I'm getting 50% (around 8 mpg I think) better mileage since my carb rebuild and exhaust work was done. Not feeling the power increase I expected though. Hills still slow her down to a crawl. 10mph up the 8% grade to North Fork seemed too slow. I can't imagine towing anything behind my rig. I never hear or feel the 4 barrel kick in like I would expect. Is it possible I'm only running on 2 barrels? Are my expectations wrong?

Thanks for your time...

-ko

[WayneG]

If you have it floored and you dont hear the secondaries open up, you probably have a linkage problem.
As for hills, a 454 with the stock transmission and a full motorhome will have trouble on hills, but I have never been down to 10 MPH

[bkahler]

With my old 310 loaded with gear and pulling a Spitfire race car on a trailer (trailer weight was about 3,500 lbs) I never got below 45 mph on any grades. The engine didn't overheat and it ran great. I know a 345 is heavier but a 310 with a 3,500 lb trailer is approaching the weight of a 345. I'd have to say there's something wrong with the carburetor setup if you can't get over 10 mph.

Brad