Chev bolt pattern 904?

Ken Parkman · 06-06-2025, 11:06 PM

They were actually quite common in cars. Came in AMC cars with the 4 cylinder from 80 thru the end of car production in 83. Also came in 4 cylinder jeeps from 81-83. They made quite a few, but that stuff is all rotted apart now. Dunno why I picked it up; probably just a conversation piece.

Mark Yacavone · 06-07-2025, 12:11 AM

Quote:

Originally Posted by Ken Parkman

They were actually quite common in cars. Came in AMC cars with the 4 cylinder from 78 thru the end of car production in 83. Also came in 4 cylinder jeeps from 81-83. They made quite a few, but that stuff is all rotted apart now. Dunno why I picked it up; probably just a conversation piece.

Okay, I was lead to believe the 904/ Chevy pattern was first used with the 153 Chevy engine .I can find no evidence of it, though. The Chevy pattern was used on the early Iron Dukes. It was continued when AMC used that engine. Non lockups with the 4 cylinder cars and Jeeps. So yes it was a "car" transmission.
Not being well versed in the foreign cars, that one slipped by me ;-)

Tom Goldman · 06-07-2025, 12:06 PM

Having worked for a AMC/JEEP dealership for 40 years and during 79-83, we saw very few AMC cars sold with the Iron Duke engine and an automatic trans.. Base model CJ5 Jeeps with the Iron Duke with an automatic also were few and far compared to stick shift BW SR4 transmissions.
The AM General DJ5 Postal Jeeps to my knowledge from 80-83 were all Iron Dukes with 904's behind them . I never saw one with a manual trans

ss3011 · 06-07-2025, 09:31 PM

The mail trucks used to come with a 153 4 cyl, and a THM 180, which is a 3 spd made in Europe, mostly for Opel. When that trans was discontinued, that is when the 904 with the Chevy bell was created. The 180 was replaced with an overdrive added on, basically a 200-4R overdrive gearset was added between the converter and the 180. That is the trans that GM sold to BMW, and the OD ratio was slightly reduced to .72 ish.

06-06-2025, 11:06 PM	#1
Ken Parkman Junior Member Join Date: Apr 2024 Posts: 10 Likes: 1 Liked 9 Times in 5 Posts	Re: Chev bolt pattern 904? They were actually quite common in cars. Came in AMC cars with the 4 cylinder from 80 thru the end of car production in 83. Also came in 4 cylinder jeeps from 81-83. They made quite a few, but that stuff is all rotted apart now. Dunno why I picked it up; probably just a conversation piece. Last edited by Ken Parkman; 06-09-2025 at 11:05 PM.

06-07-2025, 12:06 PM	#3
Tom Goldman VIP Member Join Date: Jan 2003 Location: Allentown,PA Posts: 2,477 Likes: 893 Liked 883 Times in 237 Posts	Re: Chev bolt pattern 904? Having worked for a AMC/JEEP dealership for 40 years and during 79-83, we saw very few AMC cars sold with the Iron Duke engine and an automatic trans.. Base model CJ5 Jeeps with the Iron Duke with an automatic also were few and far compared to stick shift BW SR4 transmissions. The AM General DJ5 Postal Jeeps to my knowledge from 80-83 were all Iron Dukes with 904's behind them . I never saw one with a manual trans __________________ Tom Goldman 1500 SG , 1506 STK

06-07-2025, 09:31 PM	#4
ss3011 Senior Member Join Date: Feb 2002 Location: Southeast Michigan Posts: 910 Likes: 70 Liked 239 Times in 114 Posts	Re: Chev bolt pattern 904? The mail trucks used to come with a 153 4 cyl, and a THM 180, which is a 3 spd made in Europe, mostly for Opel. When that trans was discontinued, that is when the 904 with the Chevy bell was created. The 180 was replaced with an overdrive added on, basically a 200-4R overdrive gearset was added between the converter and the 180. That is the trans that GM sold to BMW, and the OD ratio was slightly reduced to .72 ish.