85lebaront2 Posted June 27, 2018 Share Posted June 27, 2018 Gary, I hope that works. I think it will take stiffness out of the ride. If you like the result, then consider going with the F350 set up and the extra spring on top. I think the only time mine contacted was when hauling gravel. It did squat easier than my old brown ‘81 F250 with overload springs, and that was reflected in the ride quality. That F250 was a rough riding son of a gun with that extra spring pack. The extra upper spring on the F350 is plenty. I once had the guy at the quarry load me up with crusher fines that were still fairly wet after a rain. As he tilted his loader bucket the whole scoop plopped out instead of gradually pouring in as intended. The truck had the full 8 foot bed filled to the bed rails and a peak in the middle that was higher than the cab 😬. And yeah, these were wet crusher fines that were fine enough to cake together. The springs didn’t look bad at all, it was the tires that I was worried about. They were flattened out pretty badly, but I only had a couple miles to go and I kept it under 20 mph. I used to haul a 30' 5th wheel trailer, 10K loaded and I think it was 1710 lbs pin weight and it would just bring the truck down to touch the overload spring. I have also twice had the proverbial "ton of bricks" in the bed with no problems whatsoever. I keep my rear tires at the recommended 65 psi (215 85R/16 LR D) for dual rear wheels. My axle is rated 7400 lbs. Link to comment Share on other sites More sharing options...
Gary Lewis Posted June 27, 2018 Author Share Posted June 27, 2018 I used to haul a 30' 5th wheel trailer, 10K loaded and I think it was 1710 lbs pin weight and it would just bring the truck down to touch the overload spring. I have also twice had the proverbial "ton of bricks" in the bed with no problems whatsoever. I keep my rear tires at the recommended 65 psi (215 85R/16 LR D) for dual rear wheels. My axle is rated 7400 lbs. Interesting. Darth has a 7400 lb axle and Big Blue has a 6250 lb axle. But both of them show spring code K for the rear springs, and in both 1985 and 6 spring code K called for E3TZ 5560-T springs. But, in 1985 the catalog shows that those were replaced by E7TZ 5560-A's, although the catalog doesn't say they were for 1986. If General Spring is correct and K's are 3100 lb springs, then your overloads must be good for about 600 lbs each to get the total pack to 3700 and match the axle. Does that make sense? Link to comment Share on other sites More sharing options...
85lebaront2 Posted June 27, 2018 Share Posted June 27, 2018 Interesting. Darth has a 7400 lb axle and Big Blue has a 6250 lb axle. But both of them show spring code K for the rear springs, and in both 1985 and 6 spring code K called for E3TZ 5560-T springs. But, in 1985 the catalog shows that those were replaced by E7TZ 5560-A's, although the catalog doesn't say they were for 1986. If General Spring is correct and K's are 3100 lb springs, then your overloads must be good for about 600 lbs each to get the total pack to 3700 and match the axle. Does that make sense? That would make sense since 3100 X 2 = 6200, 6200 + 2 X 600 = 7400. Maybe if could get the information on the individual leaves you could arrive at a viable option. As far as ride quality, Big Blue is a standard cab or 133" wheelbase, Darth is a crew cab or 168" wheelbase, that extra 35" goes a good way towards making it feel smoother. Also keep in mind Darth is 2WD and as such has big COIL springs which probably help the front ride feel over leaf springs. My 1958 F100 rode like a buckboard, 110" wheelbase and 4 leaf springs. Link to comment Share on other sites More sharing options...
Gary Lewis Posted June 28, 2018 Author Share Posted June 28, 2018 That would make sense since 3100 X 2 = 6200, 6200 + 2 X 600 = 7400. Maybe if could get the information on the individual leaves you could arrive at a viable option. As far as ride quality, Big Blue is a standard cab or 133" wheelbase, Darth is a crew cab or 168" wheelbase, that extra 35" goes a good way towards making it feel smoother. Also keep in mind Darth is 2WD and as such has big COIL springs which probably help the front ride feel over leaf springs. My 1958 F100 rode like a buckboard, 110" wheelbase and 4 leaf springs. Yes, Big Blue has leaf springs in front, and that doesn't help the ride any. But we've watched (felt?) and the biggest jolt on bumps is when the rear axle hits. So I'm hoping to soften the blow(s) some with de-springing him a bit. But, that isn't going to happen very quickly as I have a ton of things to do first. However, I will get it done. Link to comment Share on other sites More sharing options...
Ford F834 Posted June 28, 2018 Share Posted June 28, 2018 Yes, Big Blue has leaf springs in front, and that doesn't help the ride any. But we've watched (felt?) and the biggest jolt on bumps is when the rear axle hits. So I'm hoping to soften the blow(s) some with de-springing him a bit. But, that isn't going to happen very quickly as I have a ton of things to do first. However, I will get it done. I don’t know if it helps, but here is the certification label for my 4x4 F350. Interesting that the rear spring code is the same as DRW??? Link to comment Share on other sites More sharing options...
1986F150Six Posted June 28, 2018 Share Posted June 28, 2018 But, that isn't going to happen very quickly as I have a ton of things to do first. However, I will get it done. Appropriate wording for this subject matter!! Link to comment Share on other sites More sharing options...
Gary Lewis Posted June 28, 2018 Author Share Posted June 28, 2018 I don’t know if it helps, but here is the certification label for my 4x4 F350. Interesting that the rear spring code is the same as DRW??? David - Pun intended. Jonathan - Interesting! So we have the following with the same spring code "K": '85 F250HD regular cab rated at 5922 lb GAWR w/a 6250 lb axle and LT 235/85R16E tires '86 F350 crew cab rated at 6084 lbs GAWR and with a 6250 lb axle and LT 235/85R16E tyres An '86 F350 crew cab DRW rated at 7400 GAWR and with a 7400 lb axle and 4 215/85R/16D tyres Turns out that LT 235/85R16E tires are rated for 3042 lbs, and two of those would get you 6084 lbs, which is what yours is rated at. But Big Blue is only rated for 5922 with the same axle, tires, and main spring pack, so apparently the overload is standard on an F350 and boosts the spring rating to over the rating of the tires - to at least 3700 lbs given Darth's rating. But Big Blue is running LT285/75R16E tires, and they are rated for 3750 lbs, so with the right springs it would be limited only by the 6250 lb axle. Given that, if I downgrade the main pack and then install F350 overloads or air bags I'd be there. Right? Link to comment Share on other sites More sharing options...
85lebaront2 Posted June 29, 2018 Share Posted June 29, 2018 David - Pun intended. Jonathan - Interesting! So we have the following with the same spring code "K": '85 F250HD regular cab rated at 5922 lb GAWR w/a 6250 lb axle and LT 235/85R16E tires '86 F350 crew cab rated at 6084 lbs GAWR and with a 6250 lb axle and LT 235/85R16E tyres An '86 F350 crew cab DRW rated at 7400 GAWR and with a 7400 lb axle and 4 215/85R/16D tyres Turns out that LT 235/85R16E tires are rated for 3042 lbs, and two of those would get you 6084 lbs, which is what yours is rated at. But Big Blue is only rated for 5922 with the same axle, tires, and main spring pack, so apparently the overload is standard on an F350 and boosts the spring rating to over the rating of the tires - to at least 3700 lbs given Darth's rating. But Big Blue is running LT285/75R16E tires, and they are rated for 3750 lbs, so with the right springs it would be limited only by the 6250 lb axle. Given that, if I downgrade the main pack and then install F350 overloads or air bags I'd be there. Right? Ok, here is what I am running for tyres right now old bean, the tyres have 112/115 on them since all the old load ratings seem to have been devoured by DOT. I am running 58 psi front and 65 psi rear, these may be equivalent to LR E as they give a load rating for 80 psi but it was too dark to read it clearly (more tomorrow) These are the same size and tyre that the counties use on school buses, probably the E350/GM3500 ones. Link to comment Share on other sites More sharing options...
Gary Lewis Posted June 29, 2018 Author Share Posted June 29, 2018 Ok, here is what I am running for tyres right now old bean, the tyres have 112/115 on them since all the old load ratings seem to have been devoured by DOT. I am running 58 psi front and 65 psi rear, these may be equivalent to LR E as they give a load rating for 80 psi but it was too dark to read it clearly (more tomorrow) These are the same size and tyre that the counties use on school buses, probably the E350/GM3500 ones. Those are LR E's with either a 2380 or 2680 lb rating, and you have far more tire than you have rear axle. Link to comment Share on other sites More sharing options...
85lebaront2 Posted June 29, 2018 Share Posted June 29, 2018 Those are LR E's with either a 2380 or 2680 lb rating, and you have far more tire than you have rear axle. That was my thought too. They do not ride badly at all and wear seems fantastic, I will get a picture of the front tread later today. One item I found in the past, DRW tire ratings are lower per tyre than SRW, probably due to greater heat buildup with the tyres so close together. Better more rather than less. Link to comment Share on other sites More sharing options...
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