3/4 ton engine options - repost

[chronos]

I am looking at a 1986 3/4 ton. Did these come with a 400 engine? Is there a EASY way to tell a 400 from a 350 engine?? Thanks

[VileZambonie]

No they were no longer making the 400 in 1986. The best way is to read the casting # on the back of the engine near the bellhousing.

The 400 was used from 1970 -1980 and they only made 4 bolt mains in 71 and 72 if I remember correctly.

Look for the casting #'s

Also take a look at the balancer on the crankshaft. It will not be smooth all the way around you will see it is balanced.

Some say look to see if it has 2 or 3 core plugs on the side but I forget exactly what that reveals. I haven't owned a 400 in about 10 years.

[chronos]

Thanks , Can I put the rearend from a 3/4 fullsize into a 1/2 ton shortbox?

[Blazin]

3/4 and 1/2 ton axles are the same as far as the bolt in dimensions. The ujoint will require a crossover joint.

[VileZambonie]

The 3/4 ton will have 8 lug axles and different brakes.

[Fast68]

the non 1 tons were all 42.5" leafpack spacing

1 ton were 40

1/2 and 3/4 interchange, same width


good luck