So I get under my truck and find this transmission...

[Chefman43223]

Like they said, the HM290 is a light duty transmission, would have only come in 1500's and 2500 "light duty" (7200 lb gvwr) trucks. Your truck being a 3500 wouldn't get the light duty transmission. So, being a 1988, it gets the SM465 granny low 4 speed, because the NV4500 granny low overdrive 5 speed didn't hit the scene until 1992.

Richard

Thank you !

 

[Chefman43223]

Short tail shaft, separate bell housing ( not part of transmission). And survey sez, " RPO M20 Muncie " Cast Iron.
If it hasn't been swapped out. And if you still have the glovebox data RPO tag. The other options were Getrag Aluminum, one piece bell housing transmission combo.

The tag is on the drivers side door and is heavily faded.

 

[someotherguy]

The tag is on the drivers side door and is heavily faded.

That's going to be your tire sticker. Size, inflation #'s, etc.

The SPID label (Service Parts Identification) label is on the floor of the glovebox on 88-94 models.. and is often damaged beyond legibility from stuff sliding around on top of it.

Richard

 

[Chefman43223]

That's going to be your tire sticker. Size, inflation #'s, etc.

The SPID label (Service Parts Identification) label is on the floor of the glovebox on 88-94 models.. and is often damaged beyond legibility from stuff sliding around on top of it.

Richard

Yeah, no tag in the glovebox.

 

[bamabound]

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plug your vin# in here and should tell ya all ya need to know

 

[GoToGuy]

So for the 88 the option list is short compared to later models. One page. These are the options available for your year.

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