Shops quote $1,400–$2,200 for this one, and the quote usually isn't the ripoff, the job really is that big. Here's what's actually failing, what the correct repair involves, and the honest part: this is not a job I do in a driveway.
The rear main seal rides the back of the crankshaft, sealing engine oil right at the point where the engine bolts to the transmission. It's rubber living against a spinning crank in constant heat, and on these 5.7 HEMI cars age does what age does: the seal hardens, loses its flexibility, and stops sealing. The leak shows up exactly where you can't see it without getting underneath, in the bellhousing gap between engine and transmission, and slowly paints the underside of the car.
There's no shortcut to this seal. The transmission has to come out to reach it, which is why so many owners get quoted big and put it off. The silver lining: on a rear-wheel-drive Charger or Challenger, the trans drop is a clean, straightforward job, no all-wheel-drive transfer case, no subframe gymnastics.
And while the transmission is out, the flex plate, the thin steel plate connecting crank to torque converter, gets a proper inspection, because these crack on HEMIs. A cracking plate makes a knock or vibration at idle that's often misdiagnosed, and it can chew at the area around the trans front seal, which is where an ATF smell comes from. Checking it costs nothing extra while everything's apart; missing it means doing this entire trans-out job twice.
If your Dodge is doing any of these, this is the likely cause:
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See how that range compares across Mississauga, Oakville, Milton, Brampton and Etobicoke in the GTA Repair Price Index, honest shop & dealer ranges for the jobs people actually get done.
Rear Main Seal & Flex Plate Service is on my published list of jobs I turn down. It needs a hoist, a press or a machine shop, and I work out of driveways with hand tools. That list is public on my trust page. I'd rather lose the job than learn it on your engine, and you should be suspicious of anyone who says yes to this over the phone.
So here's what I can genuinely do for you, holding a $1,400–$2,200 quote. Both are real, both are flat-priced, and both are worth more than a bad yes.
Before you spend $1,400–$2,200, have someone independent confirm that's actually what's wrong. This is a diagnosis, not the repair, no hoist, no lift, nothing comes apart. I scan it, test it, look at it with you, and tell you straight whether their diagnosis holds up. If it does, I say so and you go pay them with confidence.
Book the second opinion →At $1,400–$2,200 on a car that might be worth not much more, plenty of people replace instead of repair, that's a completely reasonable call. If that's where you're heading, get the next car measured before you hand over money: 150 published points, at the seller's location, written report the same day.
Book a pre-purchase inspection →Tell me what you've been quoted and what the car is doing. $100–$250 flat, at your location, and you get a straight answer either way.
Rather just have the quote read? The free quote check tells you whether the number is in line, no visit needed.
Jobs on this car that ARE mine:
Not so you can do it yourself, so you can tell whether the shop quoting you understands the job:
That's the job. It's why this one belongs on a hoist instead of in a driveway, and it's why $1,400–$2,200 usually isn't a ripoff, it's a big repair honestly priced. What's worth checking is whether that's really what your car needs.
Get the diagnosis confirmed firstPlain version: Rear Main Seal & Flex Plate Service needs equipment a driveway doesn't have, a hoist to get under it properly, a press or a machine shop for the parts that come out, and a controlled space for an engine or gearbox that's in pieces for days. I work out of driveways with hand tools. That's not false modesty, it's the published limit of what I take on, and it's listed on my trust page alongside the warranty.
What that means for you: this page is here to tell you what's failing and what it should cost, so you walk into a shop knowing the job instead of nodding at a number. And if you want that number checked before you pay it, that part I can do, $100–$250 flat, at your location.
A rear main leak rarely strands you, it bleeds you. Oil drips onto the exhaust, the level creeps down between changes, and if you're the type who doesn't check the dipstick monthly, a slow leak can quietly become low-oil bearing wear on an otherwise healthy engine. The flex plate angle is the sharper risk: a cracking plate gets worse with every start cycle, and a fully failed one can leave you with a car that cranks but won't move.
Yes. With a proper transmission jack and supports, a RWD trans drop is methodical work, not shop-only magic. We need flat, solid ground and a day. The car never leaves your home, and you're not paying anyone's storage-and-shuttle overhead.
It's the steel plate that connects your crankshaft to the torque converter. HEMI flex plates are known to crack, and the symptoms, idle vibration, a light knock, overlap with other issues, so cracks go undiagnosed. Inspecting it while the trans is out is free insurance against doing this whole job again in six months.
Location and pattern. Rear main oil collects in the bellhousing gap and drips mid-car; valve cover or oil pan leaks track differently. We confirm the source before quoting, cleaning the area, dye if needed, because dropping a transmission to fix the wrong leak helps nobody.
No. Rear Main Seal & Flex Plate Service is on my published list of jobs I turn down, it needs a hoist, a press or a machine shop, and I work out of driveways with hand tools. I'd rather lose the job than learn it on your engine.
Two things, and both are real. A second-opinion diagnostic at your car, $100–$250 flat, at your location, so somebody independent confirms that's actually what's wrong before you commit to a $1,400–$2,200 repair. And if you're weighing replacing the car instead of fixing it, a pre-purchase inspection on the replacement, $149–$399 flat, at the seller's location.
Because the useful part isn't the wrench. It's knowing what's actually failing, what the correct repair involves, and that shops quote $1,400–$2,200 for it, so you walk in knowing the job instead of nodding at a number. If you want that number checked before you pay it, that part I can do.
Send it over for a free second opinion. I'll tell you straight what the job actually involves, and if their quote is fair, I'll tell you that too.
Get a Free Second OpinionOther makes:
I'm not the guy who does this repair. I'm the guy who tells you whether you actually need it, before you spend $1,400–$2,200. Second opinion at your car, $100–$250 flat, in Mississauga, Oakville, Milton, Brampton and Etobicoke.
Book a Second Opinion Inspect a Replacement CarYour options on this one