Dumb question from a drivetrain noob
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Joined: Sep 2016
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Dumb question from a drivetrain noob Hello,
I have a dumb question. I'm asking for a friend who has recently had severe transmission damage, which the mechanic insists could be caused by the engine.
The mechanic it's with insists that he will not work on fixing the transmission, because it will just get damaged again until the engine is sorted.
Damage on the engine: Broken valve retainer (which I understand can lead to several issues in the powertrain...bent pushrods, valve stems, lifter damage, etc)
But, putting that aside for a moment:
Can a damaged engine also damage a manual transmission in some way/shape/form?
What about the other way around? Lets say the clutch overheated or such, or there was a critical failure in the transmission itself: Could that lead to potential engine damage?
Which is more likely?
I understand this is a vague question, but I severely lack the understanding in this area.
Edit: I'm a dork, forgot to mention damage on the transmission:
Cracked bellhousing, broken "ears" (where the bolts go in to secure the transmissions to the bell housing). The mechanic refuses to get started on it (makes no sense to me) until the engine is looked at.
But what can cause *that* extent of damage? short of running your car into a curb or something? lol
My guess is that something seized/overheated, causing the flywheel to chip pieces off/missing a few teeth, which I guess can lead to issues with the engine?
As well as physical damage to the housing etc.
Honestly reading over my post, I don't even know how to make sense of it.
I have a dumb question. I'm asking for a friend who has recently had severe transmission damage, which the mechanic insists could be caused by the engine.
The mechanic it's with insists that he will not work on fixing the transmission, because it will just get damaged again until the engine is sorted.
Damage on the engine: Broken valve retainer (which I understand can lead to several issues in the powertrain...bent pushrods, valve stems, lifter damage, etc)
But, putting that aside for a moment:
Can a damaged engine also damage a manual transmission in some way/shape/form?
What about the other way around? Lets say the clutch overheated or such, or there was a critical failure in the transmission itself: Could that lead to potential engine damage?
Which is more likely?
I understand this is a vague question, but I severely lack the understanding in this area.
Edit: I'm a dork, forgot to mention damage on the transmission:
Cracked bellhousing, broken "ears" (where the bolts go in to secure the transmissions to the bell housing). The mechanic refuses to get started on it (makes no sense to me) until the engine is looked at.
But what can cause *that* extent of damage? short of running your car into a curb or something? lol
My guess is that something seized/overheated, causing the flywheel to chip pieces off/missing a few teeth, which I guess can lead to issues with the engine?
As well as physical damage to the housing etc.
Honestly reading over my post, I don't even know how to make sense of it.
Last edited by AndyTA; Jul 6, 2022 at 07:54 PM.
There could be something wrong internally with the engine, broken mounts, etc. Unless someone can articulate an exact history of what happened, it should be gone over with a fine tooth comb to fix the source of the issue. I can't think of why a transmission would rip itself off an engine.
Joined: Nov 2003
Posts: 6,216
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From: Wichita KS / Rancho San Diego
It sounds to me like abuse factors into the equation here. That being said, it seems to me like the mechanic is on the right track. If I were he, I'd want to start the motor, scan it, rev it and check to see if the mounts are holding. It's conceivable that hard shifting with bad motor and transmission mounts could cause that kind of damage.
But if the valvetrain issue means that the motor will barely run, then the mechanic is right. Get that fixed and go from there.
But if the valvetrain issue means that the motor will barely run, then the mechanic is right. Get that fixed and go from there.
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Joined: Aug 2008
Posts: 459
Likes: 18
If the mechanic is so sure the engine caused the damage, do they tell you what's wrong with the engine? I know bad mounts can cause all kinds of damage, especially if the car is beat on. You have 1 mount on either side of the engine and one on the rear of the transmission holding the entire unit together. If any of those are loose, the entire engine/transmission assembly is going to twist and I could easily see it breaking at a weak point. If the engine uses a pilot bushing or pilot bearing for the transmission and that's not right, it will stress the input shaft on the transmission and can absolutely wipe out the transmission.
