engine freezing up after transmission rebuild

[san9]

I have known of two separate instances (on two different cars) of engine failure after a transmission rebuild. Is this sheer coincidence or are can the subsequent engine failure be related to the tranny job? Does anyone out there know?

Thanks!!

[RexNfx400]

Never seen that. Have been around about 500 or probably more, trans install on the taurus. What kind of failure? Crank thrust? Low oil pressure? How soon after rebuild?

[san9]

Originally Posted by RexNfx400

Never seen that. Have been around about 500 or probably more, trans install on the taurus. What kind of failure? Crank thrust? Low oil pressure? How soon after rebuild?

I'm sorry these cars were not Taurus'. This is a general auto question. Both cars went down within 48 hours after being picked up from the transmission shop. The first one, a 75 buick, threw a rod from what I heard the serviceperson say, this was in 1985. The second an 84 Honda Civic, lost oil pressure the day after having the transmission rebuilt, circa 1995. I was driving it when it lost the oil pressure, my husband says the service person he talked to, subsquently, (I was not there) said the engine was 'gone'.

I have always wondered if there could be a connection, my husband says he thinks not. Thanks for replying!

[amac209]

i'd say the buick already had a crack in the rod and couldn't handle the extra torque so it snapped. as for the oil pressure there should be no connection unless they damaged the rear main seal or bearings by prying however this is very unlikely. i've never heard of engine failure after a transmission job

[san9]

Originally Posted by amac209

i'd say the buick already had a crack in the rod and couldn't handle the extra torque so it snapped. as for the oil pressure there should be no connection unless they damaged the rear main seal or bearings by prying however this is very unlikely. i've never heard of engine failure after a transmission job

It makes sense that the transmission would have better performance after a rebuild. And it does make sense that the engine probably had existing problems and couldn't handle the extra power being tranfered. I guess it's always best to evaluate the whole car prior to putting a large investmant into it. Thanks so much!

[brooster42]

I did many transmission jobs, and many engine jobs. My opinion is that they are totally unrelated. The only thing in common is that both cars had worn out transmissions. Perhaps they shared worn out engines as well. There is no substance behind the idea that a trans rebuild generated extra torque that was taxing on the engine. Transmissions don't create "extra" torque - they only transfer engine power to the rear wheels. Also, connecting rods don't crack. When somebody says "it threw a rod", they cannot possibly know that unless the connecting rod literally came out through the oil pan. It happened to me once. Most likely, the rod bearing(s) failed due to wear and/or lack of oil pressure. When the bearings get old and worn, the engine cannot build oil pressure like it did when it was young and tight. Kinda like me.

[amac209]

i've seen rods snap in half and punch a hole through the side of the block. i guess it's true a new tranny doesn't create extra torque but firmer shifts will create more impact on the engine but shouldn't wreck it

[RexNfx400]

I didn't really want to put it like this. But how does this sound?
Cruising down road, Trans starts slipping, for whatever reason. Instead of pulling over and calling Mr. Hook.
You need to make it home, or somewhere safe. Rev to the moon. Get every last inch out of that tranny. At 8000 RPMs lol Maybe the engine too...

[amac209]

sounds possible to me.