Engine Frame Mounts--455 Olds in 76 GMC--May have found something!!??

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OldBlueDually

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Gents, I need your input. I have been on the search for engine to frame mounts for my truck. I was told the 1978 to 1980 GM trucks with the Olds 350 Diesel will work.

I want to know, do these Speedway ones look like the originals? They sure look spot on to me. Any opinions on this, I just want to see what others think.

Just my luck to do something out of the ordinary, then again if it was easy what fun would it be!!

I could return them I am sure if they don't work, but this by far is the closest thing I have found.



Original mounts I need, as you can see there is a left, and a right.

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Mounts from Speedway Motors.

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Ricko1966

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The bolt holes don't look to have the same spacing to me. Hopefully someone on here has a 1968-72 chevelle to take some measurements for you. Something else I would check is whether 68-72 Cutlass uses the same mount. Olds engine I'd be eyeballing Olds mounts.Ive gotten my self in to situations before where the block side of the mount wouldn't fit over the frame side of the mount.What did you get your motor out of and where are those mounts?
 

OldBlueDually

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@Ricko1966 I have an engine from a '69 Olds. It has 3 bolts each side on the block to move the mount one way or the other.

I was told I need to find the 78 to 80 GM diesel mounts, these new ones look damned near correct, but I'm not sure. If you go to Speedways website and see the different views it looks like the offset holes look similar, just not certain.

The stock mounts from a 69 Olds I'm not sure what they look like, haven't honestly looked into it, but that's a good idea.
 

Ricko1966

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Okay now what I have run into before is say I've got a block mount from a 1975 oldsmochevy and a frame mount from a 1594 pontymobile some times the through bolt length is different and the block mount won't physically fit inside the engine mount. I do not know your skill set but me I'd put the 69 frame mounts inside the motor side install the through bolt and set the engine in the bay, use my transmission mount for front to rear location check my tail shaft angle. If all good tack the frame mounts down pull the mount bolts lift the engine up or out and drill holes for the mounts. If the angle is wrong you will have to shim the frame side mounts up nbd cut plates the same size as the mount drill through holes bolt down the mount with the captured plate/shim.
 

OldBlueDually

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Okay now what I have run into before is say I've got a block mount from a 1975 oldsmochevy and a frame mount from a 1594 pontymobile some times the through bolt length is different and the block mount won't physically fit inside the engine mount. I do not know your skill set but me I'd put the 69 frame mounts inside the motor side install the through bolt and set the engine in the bay, use my transmission mount for front to rear location check my tail shaft angle. If all good tack the frame mounts down pull the mount bolts lift the engine up or out and drill holes for the mounts. If the angle is wrong you will have to shim the frame side mounts up nbd cut plates the same size as the mount drill through holes bolt down the mount with the captured plate/shim.

A 1594 Pontymobile, holy **** that's when the earth was still flat!!!! :anitoof:

Skill set, I do it all! Things like this I don't want to mess up so I ask the pro's on here that have had experience!!!

What you said is not a bad idea at all, I could easily enough set the engine, tack mounts into place, drill holes...etc.

Here is the truck this engine is going into to...

https://www.gmsquarebody.com/thread...-dually-gotta-get-it-on-the-road-again.29806/
 

Ricko1966

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Awesome truck. I'm jealous. As long as the original Olds mounts will set the engine at the correct angle this is real easy, but still shimming the mounts or altering the transmission mount is NBD. As long as the tailshaft angle matches the pinion angle it's all good.

As for saying I don't know your skill set, no insult intended. Some people can do everything and some people can't.

I've done so many crazy bastard engine swaps in my life. It's like changing socks to me.
 
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OldBlueDually

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Awesome truck. I'm jealous. As long as the original Olds mounts will set the engine at the correct angle this is real easy, but still shimming the mounts or altering the transmission mount is NBD. As long as the tailshaft angle matches the pinion angle it's all good.

As for saying I don't know your skill set, no insult intended. Some people can do everything and some people can't.

I've done so many crazy bastard engine swaps in my life. It's like changing socks to me.

Ah, no worries man, we don't know each other that well so no offense taken in the least!

Thanks for the comment, it is a very cool truck, unique in its own way. I love the fact it is a "dually kit"....I haven't seen any before, so I am leaving it that way with those rims & I will shine up the hubcaps on it, and put some thin stainless beauty rings on the rims too, I think it will look sharp. If I don't like the looks, I can easily change it.

As for the rearend in the truck, I have not actually tacked or welded my perches yet on the rearend, because I want to get the engine dropped into place & hooked up as you stated, then I want to rotate that rear axle and make sure all is good with the angles you mention....then start tacking things into place.

I have a bit more work to do, and some coin to blow on this thing yet, but I am hoping to have it on the road this spring!
 

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