Warlockk

Dadgummit my trans is going out. It has been taking too long to shift into second at a cold start. I checked the fluid and it was a bit on the high side and airated ( foamy ). Driving home today it started slipping out of gear and jumping between gears so I finally picked up a pump and pulled out a few ounces. It ran well enough to get me 4 miles home. I am hoping letting it set the air will work its way out and maybe I'll get lucky. I really don't want to rebuild this trans. Have you guys had any luck with you pull it trannies. Is the AOD a weak trans?

bigmike7362

not in the least mine has 456742 on it and has never been rebuilt my buddys dad owned the truck before me and he said it was never rebuilt since he bought
the truck new and i beat the hell out of my truck

Just call me Sean

iTrader: (1)

I don't like getting automatics from u-pull-it places. They usually don't keep track of what parts are good so if you get a bad one you have to pull it again until you get a good one. Still have warranties but a big pain in the ***. Chances are if the truck is an automatic that's why it's in the junkyard.

dr_bowtie

AOD transmissions are pretty bullet proof. They can handle a lot of power and a lot of racers use them because they are strong.

Word to the wise, because i learned the very hard way, they flywheel and torque converters are MATCHED and they make 3 different set/types and they all look alike but the thickness is different and not by a lot.

Trucks go with trucks, cars with cars and vans with vans and Cop cars are different yet.

If you mix them it blows the pump on the first firing of the engine. I leaned the hard way after 4 transmissions and a 2,000.00 transmission shop bill later. I still have the F100 AOD that caused the problems fully rebuilt with a cracked pump just from the issue...

EDIT: I forgot to add I NEVER buy an engine or transmission i cannot hear nor drive.... trans, If i cant drive it to feel the shift no way.... I dont like changing them 3-4 times for some i just buy a new one rather than deal with them.... those like the GM 700R4 it's better and cheaper to buy a TCI unit than to have the original rebuilt... there are 45 upgrades that need to be done and shops want 2,500.00 to rebuild them not including upgrades and I can buy a NIB one with all the upgrades for 1,800.00

Warlockk

OK bought myself a little time and a little fun. I picked up brand new Yamaha V star. I know its got rice water in the name but those cruisers are all american style. I went in looking at a used bike but the salesman for me into this one for a much lower payment and helps build up my credit. So the trans will go onto the workbench and take my time learning how to fix it. With the mild southern California weather I can ride the bike till Christmas.

dr_bowtie

buy a rebuild book as they come very illustrated and google search for needed tools...

imp

Historically, AOD was replaced by E4OD in trucks. E4OD seems to be designed for higher torque rating, is basically the old C-6 made electronic. AOD has no electrical inputs/outputs pertaining to the transmission itself, it is fully mechanical.

Introduction of AOD was important because it eliminated torque converter energy losses in upper gear ratios, doing so by using a coaxial (one inside the other) input shaft. This meant one was skinny, but it drove only 3rd and 4th gears, I believe. The shift to 3rd. gear with AOD always felt to me like something of a "bog", as it eliminated the torque converter's "slip" at the same time it shifted to a higher gear.

All later useage transmissions use electronically controlled clutches within the torque converter housing itself, engaged or disengaged hydraulically by a solenoid controlled by the computer. Thus, programming could allow great leeway in when the damn thing engaged, based on engine load, vehicle speed, throttle position, and who knows what all else they consider as well.

FWIW, some guys disconnect the Torque Converter Clutch Solenoid and substitute a switch in the cab. That at least allows the TCC to remain engaged all the time the vehicle is moving; come to a stop with it engaged, kills the engine, just like a stick shift would with clutch engaged. The manual switch confounds the computer though, so it throws trouble code, which must be ignored.

So, maybe my long-winded blab is helpful in understanding these things. Maybe not. imp

dr_bowtie

I'd rather have it lock up like that....

The GM version locks the convertor in 2nd gear and it's worse. I make them lock in 3rd gear and 4th only

Warlockk

For anyone interested I just got my newly rebuilt trans in and the old girl runs better than I have ever seen it. My trans tech said it burned up the band and needed some hard parts as well. A lot of debris found in the fluid too. I hope to get more details but it appears to me an out of adjustment TV cable was the culprit. Along with a poor rebuild by AAMCO. the cable was too tight making it run too high before shifting and causing hard shifts. This went unnoticed due to the poor rebuild. Once the new rebuild was in it was smooth as silk until overdrive. Then it felt like it was hitting a speed bump at 60 mph. I pulled the TV cable adjuster and it sprang out about 1/2 inch that shouldnt have been there. Once set to spec it was smooth sailing. A new rear main seal and new u joints completed the job and she idles, cruises and accelerates better than ever. I think the main seal was affecting oil pressure a little. Or maybe it just liked the attention.