JEGS
GM 700R4, 4L60, 4L60E Transmission Crossmember
555-640601
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G-Body Crossmembers
JEGS 555-640601 Transmission Crossmember Features:
- The double-hump design allows dual exhaust upgrades for your vehicle
- Black powder-coated steel for strength, great looks, and long life
- Must have upgrade for transmission swaps
Installation Notes:
- Some 1983 Hurst Oldsmobiles were originally equipped with a 2004R transmission and will not require this frame extension. If you are unsure, 1984 and later models will feature two mounting locations for the transmission cross member approximately 14 in. behind the front set of mounting holes.
- Crossmember is designed for 1978-1988 G-Bodys that were originally equipped with an Chevy small block engine.
- Does not fit Cutlass Supreme models or El Camino.
- Engine and transmission swaps may require some additional modifications & fitment of components. Hardware is not included.
FAQ
Is 4L60 and 700R4 the same transmission?
- Yes, the 4L60 and 700R4 are essentially the same transmission, differing mainly in nomenclature. The 700R4 was the original designation, while the 4L60 name was introduced later to reflect improvements and changes in the transmission. Both are four-speed automatic overdrive transmissions commonly used in GM vehicles.
Can you convert a 4L60E to a 700R4?
- Converting a 4L60E to a 700R4 is technically possible but involves significant modifications and compatibility considerations. The 4L60E is an electronically controlled transmission, while the 700R4 is mechanically controlled. Converting between them would require rewiring, mechanical alterations, and potentially sourcing additional parts. It's advisable to consult with a qualified mechanic or transmission specialist for guidance.
Can you put a 4L60 in place of a 4L60E?
- Swapping a 4L60 in place of a 4L60E may be feasible with the right modifications and compatible components. However, it's crucial to consider differences in electronic controls, wiring, and transmission functionality. Depending on the vehicle's setup and desired outcome, this swap may require extensive adjustments and could affect overall performance. Consulting with a knowledgeable technician or utilizing conversion kits designed for this purpose is recommended.
Is transmission crossmember important?
- Yes, a transmission crossmember is vital for proper support and alignment of the transmission in your vehicle. It helps distribute the weight of the transmission, maintains drivetrain alignment, and reduces stress on mounting points. The correct crossmember ensures structural integrity and prevents issues like vibration, driveline misalignment, and potential damage to transmission components. Explore reliable transmission crossmembers, including the G-Body 4l60E crossmember and G-Body 700R4 crossmember, available at JEGS.com.
Specifications:
Part Type
Product Line
Amount of Drop
Stock
Bolts Or Studs Included
No
Crossmember Finish
Black powdercoated
Crossmember Material
Steel
Mounting Bracket Included
No
Package Depth
4.00
Package Height
49.60
Package Width
10.10
Part Category
Replacement Parts
Part Fitment
Direct Fit
Quantity
Sold individually
Shipping Weight
15.91
Transmission Crossmember to Frame Bushing Included
No
Transmission Mount Included
No
Width
45.25 in (1149.35 mm)
640601 is rated
out of
5 by
35.
Rated 5 out of
5
by
Scott from
1978 Monte Carlo 700R4
Perfect fit, bolted right up. holes lined up perfectly. Simple install, great quality. very happy with this purchase
Date published: 2023-07-22
Rated 5 out of
5
by
Dwill713 from
G body crossmember
Part looks good so far I haven’t installed it yet but I’m impressed as of now.
Date published: 2023-03-23
Rated 5 out of
5
by
Jimmy R from
Great product
Great fit exactly what I needed for my finishing touches.
Date published: 2023-02-01
Rated 5 out of
5
by
aerocoupe mike from
great
great , bolt it on and install dual exhaust and go.
Date published: 2021-01-15
Rated 5 out of
5
by
ecalmese from
Best price around
Everywhere else I looked this product ranged anywhere from double to triple the price. I took on shot on this one and with a slight modification to get my 4l60e mounted in my 1987 Monte Carlo SS this works perfect
Date published: 2020-05-16
Rated 5 out of
5
by
Littlebill86 from
The product fits great!!! Bolts right up no problem.
Date published: 2020-03-03
Rated 5 out of
5
by
Wheelchair Guy from
Perfect fit
79 Malibu G body? or A special? Depending on who you ask.6.0 ls swap 4l60E, no extra drilling or mods. Decent welds,clean finish, strong. Shipped faster then expected, bubble wrapped. Could't be easy'er or fit better.
Date published: 2020-02-29
Rated 5 out of
5
by
Bo Jangle from
Better than expected!
This crossmember looks and fits great, awesome for the price.
Date published: 2020-01-04
Will this work on an 1987 caprice ls brougham with a 4l60e?
The Jegs 555-640601 crossmember does not fit an '87 Caprice.
Date published: 2024-02-13
Will this work in a 84 regal ls swap with 4l60e?
The Jegs 555-640601 crossmember will fit an '84 Regal with 4L60E swap.
Date published: 2024-01-05
Will this fit a 85 Monte Carlo SS with a 4L70-e transmission swap?
The Jegs 555-640601 crossmember will fit an '85 Monte Carlo with 4L swap.
Date published: 2023-06-27
Will this or do you have one that fits a t56
The Jegs 555-640601 crossmember does not fit a T56 transmission.
Date published: 2023-03-02
Will this crossmember and a 4l80e frame extension work with a 4l80e by chance? Wanting to put a 4l80e in my 79 elcamino and use the 4l60e crossmember and frame extension
The Jegs 555-640601 crossmember does not work with a 4L80E transmission.
Date published: 2023-01-10
What is different that this won't fit an El Camino? Do you have a dual exhaust crossmember that does fit a 700R4 into an El Camino?
Does not fit Cutlass Supreme or El Camino Models.
We do not offer a crossmember that fits an El Camino.
Date published: 2023-08-29
Will this fit an 81 monte carlo the vehicle came with a 3.8L v6 and th200, im swapping in a 5.3 ls with 4l60e, will this work
Yes, this will fit your Monte Carlo.
Date published: 2018-10-22
Will this fit a 4L60E?
Yes, this will fit the 4L60E and the 700R4 transmissions.
Date published: 2018-08-13
Some parts are not legal for use in California or other states with similar laws / regulations
Motor Vehicles
WARNING: Motor vehicles contain fuel, oils and fluids, battery posts, terminals and related accessories which contain lead and lead compounds and other chemicals known to the State of California to cause cancer, birth defects and other reproductive harm. These chemicals are found in vehicles, vehicle parts and accessories, both new and as replacements. When being serviced, these vehicles generate used oil, waste fluids, grease, fumes and particulates, all known to the State of California to cause cancer, birth defects, and reproductive harm.
Tools:
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Electrical Cords
WARNING: The wires of these products contain chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. Wash hands after handling.