4.5 to 4.9
Cadillac
 

Cadillac Forums | Help Us Help You | Advertise | Cadillac Parts | Cadillac News | Cadillac Classifieds / (Old System)

Cadillac Technical Archive | Cadillac Dealers | Cadillac Reviews | Cadillac Dealer Reviews | Cadillac Vendors

CadillacForums.com is the premier Cadillac Forum on the internet. Registered Users do not see the above ads.
+ Reply to Thread
Results 1 to 4 of 4
HT4100 4.1, 4.5, 4.9 Discussion, 4.5 to 4.9 in Cadillac Engine Technical Discussion; Guess what guys my guy has a nice 89 deville in real good shape with a broke transmission, and the ...
  1. #1
    ThrowSumD'sONDatBiSH is offline Cadillac Owners Member
    Automobile(s): Cadillac
    Join Date
    Aug 2007
    Posts
    31

    4.5 to 4.9

    Guess what guys my guy has a nice 89 deville in real good shape with a broke transmission, and the car is only 300 dollers i will buy it. I know how the 4.9 and 4.5 engines are suppossed to be interchangable. Well I got a 4.9 with the transmission so my question is this: Will my 4.9 engine with the transmission fit right in without any mods? Do I need to change the computer too? what all would i need?

  2. Remove Advertisements
    CadillacForums.com
    Advertisements
     

  3. #2
    Edahall's Avatar
    Edahall is offline Cadillac Owners Enthusiast
    Automobile(s): 93 & 88 Allante, 88 Eldorado
    Join Date
    Jan 2004
    Posts
    779

    Re: 4.5 to 4.9

    This is definitely not a plug and play swap. Your 89 Deville came equipped with a 4T60 non electronic transmission while the transmission matted to the 4.9 is a 4T60E electronic transmission. As a result, the transmission on the 4.9 will not shift with the computer in your 89 Deville. The computer on your 89 as well as wiring is different than a car with a 4.9 engine. You have a couple of choices though to make it work.
    1. Get a donor car with the 4.9 and change over all the wiring and computers so that it'll work with the 4.9 and 4T60E transmission.
    2. Swap the 4T60 non electronic valve body with the 4T60E transmission. I have never heard of this being done but I don't see why it would not work. They are basically the same transmission but different valve bodies. You could use either the 4.5 engine or 4.9 engine with this setup.
    3. Rebuild your 4T60 transmission and use the 4.9 engine. You would have to use the intake manifold and TBI off your 4.5. You'll also need to add an adjustable FPR to get the extra fuel requirements of the larger engine dialed in.

    Hope that you are mechanically inclined if you do choose to do any of these choices.

  4. #3
    caddeville's Avatar
    caddeville is offline Cadillac Owners Enthusiast
    Automobile(s): 1991 Deville / 1989 BMW 635csi
    Join Date
    Jan 2005
    Location
    British Columbia, CANADA
    Age
    24
    Posts
    896

    Re: 4.5 to 4.9

    A hoist to lift the vehicle will amke your life alot easier is this project is a go.

  5. #4
    I~LUV~Caddys8792's Avatar
    I~LUV~Caddys8792 is offline Moderator
    Automobile(s): 1992 Town Car Cartier & 2014 Accord LX MTX
    Join Date
    Dec 2004
    Location
    Roseville, MN.
    Age
    27
    Posts
    34,086

    Re: 4.5 to 4.9

    Quote Originally Posted by caddeville View Post
    A hoist to lift the vehicle will amke your life alot easier is this project is a go.
    Yes, and make sure it's not wet, because nobody wants to deal with a moist hoist. It just makes everything harder.
    "They call Alabama the Crimson Tide, call me Deacon Blues."

    Current:
    1992 Lincoln Town Car Cartier Edition (5/14- ?)
    2014 Honda Accord LX MTX Sedan (1/14 -?)

    Past:
    1995 Buick Roadmaster Limited (4/04-12/04)
    1992 Cadillac Sedan deVille (12/04-9/07)
    1999 Mercedes Benz S320 (8/07-7/09)
    2000 Buick Regal GS (7/09-4/12)
    2003 Mercury Marauder (4/12-10/13)
    1991 Buick LeSabre Custom Sedan (9/12-6/13)
    2013 Honda Accord LX Sedan (6/13-1/14)

Quick Reply Quick Reply

Register Now

Please enter the name by which you would like to log-in and be known on this site.
If you do not want to register, fill this field only and the name will be used as user name for your post.

Please enter a password for your user account. Note that passwords are case-sensitive.

Please enter a valid email address for yourself.

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Bookmarks

Cadillac Posting Rules

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts
Read about Lincoln | Buick | Kia Forte Forum
Need products for your Cadillac? Check out your options at the links below:

custom floor mats | Cadillac Chrome and Black Chrome Wheels | window tinting