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#59893 05/01/2006 3:54 AM | Joined: Jul 2004 Posts: 102 Member | | Member Joined: Jul 2004 Posts: 102 | I have the opportunity to buy a 1988 GMC r20 (3/4 ton). It has a 350cid and automatic transmission in it. My question is exactly which transmission is this?
The VIN is 1GCGR23K6JJ131961 and it is the original engine and transmission.
I’m looking at putting this combo (as well as other parts) into my '48 chev.
Any pointers as to where I might find this info? (Unfortunately I didn’t think to get the transmission casting numbers while I was looking at the truck)
Thanks for any help!!
1948 3600 thriftmaster
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#59894 05/01/2006 4:17 AM | Joined: Oct 2003 Posts: 363 Member | | Member Joined: Oct 2003 Posts: 363 | You don't need to look at the casting numbers, look at the pan, then compare it to any of the million pan identification charts on the internet. I do not think the trans type is embedded in the vin other than the dealer might be able to pull up the manufacturing record on 88+ vehicles, I think the cutoff is 92+
I just did a little research it can only be a Turbo 400 or 700r4. If the pan looks like Texas its a Turbo 400. | | |
#59895 05/01/2006 4:57 AM | Joined: Oct 2003 Posts: 5,152 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Oct 2003 Posts: 5,152 | Does the shift selector show an overdrive position? If so it would be the 700r4. Otherwise its probably the Turbo 400.
1955 1st GMC Suburban | 1954 GMC 250 trailer puller project | 1954 GMC 250 Hydra-Matic | 1954 Chevy 3100 . 1947 Chevy COE | and more...
It's true. I really don't do anything but browse the Internet looking for trouble... | | |
#59896 05/01/2006 8:46 AM | Joined: Apr 2005 Posts: 2,832 'Bolter | | 'Bolter Joined: Apr 2005 Posts: 2,832 | The pan shape is the quickest way to ID but the 350 turbo will have a vacuum modulator at the right rear just above the pan rail, and the 700R4 will have a square four pin electric plug on the left side center. The later 700's have a round plug with 10(or 13) pins. If it has neither of these it's a turbo 400. Every parts store that sells trans filters and gaskets has a page in the book that shows pan shapes and the trans that has that shape. It's your best bet if unfamiliar.
Evan
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#59897 05/01/2006 1:37 PM | Joined: Jul 2004 Posts: 102 Member | | Member Joined: Jul 2004 Posts: 102 | Thanks guys, I'm now pretty sure its the 700r4.
1948 3600 thriftmaster
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