Community Forums

subford · 07-09-2013, 09:19 AM

Has anyone installed the Blue-OX BX1115 base plate on the 1999-2003 Jeep Grand Cherokee.
It comes with four 3/8-16 x 2” Hex Bolts, Grd. 5 to hold it on.

This does not sound like much to me, the 1986 BII I was towing had four 12MM-1.75 X 50MM (near 1/2" bolt size) HEX BOLT GD.8.8 ZP to hold the base plate on.

Is anyone towing the 1999-2003 Jeep Grand Cherokee with these 3/8" grade 5 bolts and have you had any problems with the bolts?

Has anyone replaced them with grade 8 bolts?

TN Bill · 07-09-2013, 01:37 PM

I don't think there is a problem with Gr5 bolts but if you are not comfortable change them out. 4 Gr8 bolts would not cost much.

Dupdyke · 07-09-2013, 01:47 PM

Do some internet research on the shear strength of grade 8 vs grade 5 bolts. 8 will snap quicker but are a lot stronger I put five grade 5 on each side of my base plate did not take a real lot of work to put more holes in to have bolts bottom and sides to prevent twist or strain. D

vsheetz · 07-09-2013, 08:43 PM

I would trust the Blue Ox design engineers to have it right...

jmckinley · 07-10-2013, 07:47 AM

Grade 8 is way stronger than 5, approximately 50%. The important thing is clamping force which is what keeps the bolted joint from slipping. Go to Grade 8 with hardened flat washers both ends and loctite. Torque to 100 ft lbs. Blue Ox and Roadmaster both still use split lockwashers which were proven to be ineffective over 20 years ago. Throw them away, in this case they don't know what they're doing. Remember they're part of the RV industry and you know what that means when it comes to Engineering Excellence.

ChasA · 07-10-2013, 09:44 AM

The metric 8.8 grade is the same as American grade 5.

wyorancher · 07-10-2013, 10:16 AM

Quote:

Originally Posted by subford

Has anyone installed the Blue-OX BX1115 base plate on the 1999-2003 Jeep Grand Cherokee.
It comes with four 3/8-16 x 2” Hex Bolts, Grd. 5 to hold it on.

This does not sound like much to me, the 1986 BII I was towing had four 12MM-1.75 X 50MM (near 1/2" bolt size) HEX BOLT GD.8.8 ZP to hold the base plate on.

Is anyone towing the 1999-2003 Jeep Grand Cherokee with these 3/8" grade 5 bolts and have you had any problems with the bolts?

Has anyone replaced them with grade 8 bolts?

Grade 3/8 inch bolts grade 5 have an approx shear strength of 7900 pounds. 4 of those bolts about 31000 pounds. How much does your toad weigh?