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360 engine swap with 318 trans problem

Mason

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I have a 318 b-body trans that came with my 318 originally until i had it swapped for a 1974 360 engine, something is VERY wrong. Smoke was coming out of my trans fluid dipstick after putting it in gear, when i put the gas pedal down it felt like the brakes were locked up and would barely move after putting the gas pedal down much farther than it should need to. My engines revs also seemed to drop off very fast once i let off the pedal, almost like something is restricting it. Any help is much appreciated as this is my last thing i need to do, ive read some forums about torque converters and or flex plates but i would like to go with the cheapest solution.
 
Maybe the brakes are locked on? Has this happened immediately after the engine swap or has the engine been in for awhile? A bit more info is needed.
Cheers
 
two things
first off if you say you have a 360 motor and a 318 trans,did you Use the 360 torque convertor?
they are weighted,the 318 vertor is not.
second,did you Seat the torque convertor FULLY into the transmission? Before you bolted it up?
you should Feel it go in Twice,you spin as you go and Push gently while lifting just a hair.
first set then second set inside the vertor as it slides onto the input shaft.
this is Crucial and may be whats wrong with yours.
 
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Maybe the brakes are locked on? Has this happened immediately after the engine swap or has the engine been in for awhile? A bit more info is needed.
Cheers
This is the first time ive put it in gear to drive it, only other time ive had it in gear was with the back tires up on jacks to see if the transmission was working well and it seemed to, but when its on the ground it doesnt seem to work at all. But to answer your question ive done a full rebuild of the brake system, new master cylinder, lines, shoes, and internals so im positive thats not the case. Shouldnt cause a trans to smoke at least. Thanks for the help
 
two things
first off if you say you have a 360 motor and a 318 trans,did you Use the 360 torque convertor?
they are weighted,the 318 vertor is not.
second,did you Seat the torque convertor FULLY into the transmission? Before you bolted it up?
you should Feel it go in Twice,you spin as you go and Push gently while lifting just a hair.
first set then second set inside the vertor as it slides onto the input shaft.
this is Crucial and may be whats wrong with yours.
Ive had a guy that has a mechanics shop do it that i know well and was very familiar with mopar as he had a RR, superbee, and 2 chargers, but his knowledge abt conversions might have been his shortfall. We used the original torque verter from the 318 and didnt mess with it thinking it would be straight forward but thats obviously not the case. So i should get a 360 verter is basically what your saying? Ive been reading on other forums too abt this issue and they are talking about flex plates too as if one or the other would fix my problem. Just to add on is that the car would barely move inches and thats not an exaggeration and it started to smoke. Would this cause that issue?
 
Deal is the factory used a big weight on the 360 convertor... But you can keep the 318 convertor by using a flexplate with the balance compensation built in....

https://www.summitracing.com/parts/bmm-10236
Screen Shot 2019-08-21 at 20.07.26.png
 
i m telling you now you have a major issue and its probably not Just the wrong convertor.
i dont think you guys have it fully seated.
you will have to drop the tranny anyways to change either,
make sure you also drop the tranny pan itself and recheck for metal or sludge buildup.
your options are
A the convertor or
B the flexplate like wild shows there.

personally,at this point,id get a new convertor if it was me.
BE Sure the new convertor is fully seated into the transmission and use a small clamp to keep it there before you ever even slide it underneath the car.
and Full of trans fluid as well.
 
i m telling you now you have a major issue and its probably not Just the wrong convertor.
i dont think you guys have it fully seated.
you will have to drop the tranny anyways to change either,
make sure you also drop the tranny pan itself and recheck for metal or sludge buildup.
your options are
A the convertor or
B the flexplate like wild shows there.

personally,at this point,id get a new convertor if it was me.
BE Sure the new convertor is fully seated into the transmission and use a small clamp to keep it there before you ever even slide it underneath the car.
and Full of trans fluid as well.
 
I tend to agree, the convertor isn't fully seated... Hopefully it didn't damage the pump... The convertor probably isn't hurt, put the pump could be... Actually if it's a 904 then the convertor hubs are prone to failure so it's possible... Never seen a 727 hub damaged by not getting it fully seated...

A good trick for keeping the convertor fully seated is to use a 3/8" wrench, put a bolt through the closed end & bolt the wrench to one of the lower bell housing bolt holes so the wrench angles inward toward the convertor... One of these days I need to snap a photo... I learned that trick off an old-timer when I was 16, that's been awhile ago LOL... Used it ever since....
 
i m telling you now you have a major issue and its probably not Just the wrong convertor.
i dont think you guys have it fully seated.
you will have to drop the tranny anyways to change either,
make sure you also drop the tranny pan itself and recheck for metal or sludge buildup.
your options are
A the convertor or
B the flexplate like wild shows there.

personally,at this point,id get a new convertor if it was me.
BE Sure the new convertor is fully seated into the transmission and use a small clamp to keep it there before you ever even slide it underneath the car.
and Full of trans fluid as well.
okay yeah that would seem to be my options, i guess ill have to wait and see if the converter is my only problem. Only one way to find out i guess. But im positive thats at least one of the problems, ill keep this thread updated abt it. Thanks a whole lot!
 
if you guys just drop the trans and leave the engine in,remember to either pull the distributor and hey Mark where the rotor points!
or put a block of wood between the firewall and the rear of engine so the distributor doesnt get bent when you drop the trans.
 
I tend to agree, the convertor isn't fully seated... Hopefully it didn't damage the pump... The convertor probably isn't hurt, put the pump could be... Actually if it's a 904 then the convertor hubs are prone to failure so it's possible... Never seen a 727 hub damaged by not getting it fully seated...

A good trick for keeping the convertor fully seated is to use a 3/8" wrench, put a bolt through the closed end & bolt the wrench to one of the lower bell housing bolt holes so the wrench angles inward toward the convertor... One of these days I need to snap a photo... I learned that trick off an old-timer when I was 16, that's been awhile ago LOL... Used it ever since....
Yeah im just about to turn 18 in a few months haha, guess you passed it on to another youngin. The info you two gave is about the best ive been lookin for. I only had the car running for about 10 mins because i had just finished welding and installing my exhaust. About 3 mins of that was trying to get it in gear till it started to smoke so im sure its ok. You think the seating and the verter itself are both causing these symptoms? This trans has only 50k miles on it original and it was parked since 97. Dont think much else could be the problem
 
if you guys just drop the trans and leave the engine in,remember to either pull the distributor and hey Mark where the rotor points!
or put a block of wood between the firewall and the rear of engine so the distributor doesnt get bent when you drop the trans.
Thanks for the tip in advance! Probably wouldve ended up having that happen.
 
I have a 1970 dodge coronet but not sure what trans it is, but i know its original
im 99% its a 727 torqueflite.
itll have a bumpout on the trans pan underneath very easy to see from pass side under car.
904 is a squareish pan no bump.

btw,tip for future.
if you end up needing a tranny,hopefully not! but
if so,check out those little 1970-s-80-s dodge rv-campers the small van ones.
every one of those came with a heavy duty 727 in them and a Lot were 360 powered as well.
what i do,is buy the whole camper dirt cheap/After ive made sure the trans works and then yank the drivetrain and scrap the camper.
 
im 99% its a 727 torqueflite.
itll have a bumpout on the trans pan underneath very easy to see from pass side under car.
904 is a squareish pan no bump.

btw,tip for future.
if you end up needing a tranny,hopefully not! but
if so,check out those little 1970-s-80-s dodge rv-campers the small van ones.
every one of those came with a heavy duty 727 in them and a Lot were 360 powered as well.
what i do,is buy the whole camper dirt cheap/After ive made sure the trans works and then yank the drivetrain and scrap the camper.
Well been trying to send a picture thru this site but having a hard time, it has an indent that runs along the edges if thats what you mean so i guess ill keep that in mind if it comes down to it
 
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