What Coupler Lock do I Need for My Big Tex with Collar Style Ram Coupler for 2 5/16" Ball?

Updated 10/07/2025 | Published 10/04/2025

Products Featured in This Question

Blaylock Total-Encasement Coupler Lock for 2-5/16" Bulldog Collar-Lok Couplers - Push Button

(281)

$53.11

AMPLock Trailer Coupler Lock for 2-5/16" Ball Couplers w/o Lip - Ductile Cast Iron

(20)

$347.00

Question:

I hate to ask this question as it appears it may have been asked already, but a fraction of an inch is a make or break. I have a Big Tex 10TL-20 tilt trailer. The bulldog coupler on it is labelled RAM,12500, Made in China. Since the trailer is used, I have no idea if this coupler is OEM. A previous reply indicates that the inside width of the BLTL-23 is 3 and 1/4. That width is too narrow for my coupler. I need something a little over 3 and 5/16. I would like to verify that the inside width is exactly 3 and 1/4inch as quoted earlier. Thanks,

asked by: Lowell

Expert Reply:

Hello Lowell,

I took a stroll out to the warehouse where I confirmed that the measurement is indeed 3 1/4' from inside to inside on the # BLTL-23. If you have the collar style coupler with the 2 5/16" ball, the # BLTL-23 should work. This might seem like a silly question, but are you sure that your measurement is accurate? I only ask because sometimes a tape measurer can be off, I would try measuring from the 1" mark and not from the end, just to double check.

If you do indeed have 3 5/16", then the AMPLock Trailer Coupler Lock for 2-5/16" Ball Couplers w/o Lip - Ductile Cast Iron # AMP34FR is going to be a better option for you.

Fingers crossed that your tape measurer is off a bit, please let me know what you find out.

expert reply by: Kate F

Inside Dimension on # BLTL-23
(click to enlarge)

Lowell

10/7/2025

Hi Kate, Thanks for the reply. And thank you very much for taking the time to go out to the warehouse to check. I was using a engineer's ruler to make the measurement. I just went down and did the measurement again with a digital caliper. Caliper shows 3.34". So coupler is about a tenth of an inch too wide for the BLTL-23. After doing a bit of additional research, the coupler I have appears to be the same as the CTA-296 you stock. The AMP34FR is a bit more than I'm willing to spend. I need to spend that kind of money on a set of tie down chains and tensioners first. I'm wondering if it would compromise the strenth of the coupler to use a grinder to remove 0.05" of material off of the two corners (at the widest point of the coupler) to get the BLTL-23 to fit? The steel is substantially thicker there than the flat sides of the coupler. Will have to think on that one. Thanks again, Lowell

Kate F.

10/7/2025

@Lowell My pleasure, Lowell! I can’t recommend modifying the coupler since it could affect its integrity. Sounds like you definitely know your stuff, not everyone I talk to does! Let me know if you need any other measurements.