What size are the doghouse hold-down bolts?

[dickcarl]

My 1988 Itasca (Chevy, 454) came without any doghouse bolts.  I found some that were "close" and slid them in, but in high winds my doghouse sometimes levitates.

I tried a Chevy dealer, but they were no help.  Kept insisting it had clamps like the old vans.

[Rickf1985]

If it bolts straight down through L brackets into the floor in four places then it is the same as mine and they are 5/16-18. That does not take into account that the original holes may be stripped. it will only be 5/16 or 3/8. If one is to small and the other is too big then the holes are stripped. Tap them out to 3/8-16. I plan on changing mine to Jeep style hood latches to make access much easier, hold better to the firewall (I plan to put latches there too) and also make access tool free.

[dickcarl]

Thanks!  I buster more knuckles on those latches over the years...

[JerryP]

I plan on changing mine to Jeep style hood latches to make access much easier, hold better to the firewall (I plan to put latches there too) and also make access tool free.

Working on that plan right now.
Ordered what i thought was jeep style, but they were smaller than expected. Luckily I ordered some different ones for another project,
Like you, I want quicker easier access without needing a tool

[Rickf1985]

I should have said OLD Jeep style. The spring loaded ones, not the flip over center newer style.