Will my 4-speed withstand a chevy 350 carb'd? Just the swap... is it worth the swap? (1 Viewer)

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Apr 13, 2010
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is a stock fj 40 with 4speed manual trans. i've had some doubts if the transmission will withstand the extra torque a chevy 350 will add. the rest is all stock, oh well, i'm going for a SOA lift, i figure it'll give me an extra 5 inches, with 35's bfg's
 
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I'm not so sure that a carbed 350 is so much more power that a failure will happen at the tranny. Just my .02. If the motor is hot enough to grenade the tranny you're gonna have plenty of other axle/ring & pinion/u-joint issues anyway.

A cursory search will give you hours of reading on the subject (including guys that retained the 2f motor but went with a chevy 465 or 420 tranny). I would start with one of those to check it out. It should tell you the details. As I recall it's as easy as a pilot bearing and some other sundries.

It just seems to me that keeping the chevy tranny and using a conversion plate at the transfer case would be the easiest way to go about it.
 

Cruiserdrew

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There are thousands of FJ40s with small block chevy's in front of Land Cruiser 4 speeds, doing just fine. This is not a problem.

However, an SM465 or SM420 is a much more robust transmission than any Land Cruiser 4 speed. You just need to get used to the unsyncronized 1st gear.

For drivability the LC 4 speed is great. For pure beef, the SM465 just can't be beat and the granny first gear is a major plus when off road.

I would worry a lot more about the transfer case.
 
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thanks a lot! there's a problem, SM's are impossible to find here in Venezuela xD that's whay my question is it worth it to swap the engine or not... cuz' i think thats all i'll swap.
 
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thanks a lot! there's a problem, SM's are impossible to find here in Venezuela xD that's whay my question is it worth it to swap the engine or not... cuz' i think thats all i'll swap.
The other way i can go, is to put 3f cams and 4.5 carb. Here people do that a lot and the power gain is pretty considerable. 35's can be moved easily!
 
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Depends on how you press the skinny pedal. Anything can fail

Yes! this is the thing, i need reliability, cuz we ussually go a make 4k miles of off-road trips... were it could be featherlike pedal, or the engine rev'd to the limit for minutes in infinite mud bombs... =S
 
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Four speed Toyota trans is fine with chev 350. Three speed trans is marginal.

Running the 350 at wot is not the problem in itself. Popping the clutch at 4000 rpm could kill the trans though.

As someone else mentioned, the transfercase is the weaker link.

I've had a 300hp 350 since 1996. It's been extremely reliable. I did 3000 mile (5000 km) road trip including driving it for 25 out of about 27 hours. The truck didn't complain one bit. I'd change the oil and do it again if the oportunity arose.
 

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