Good day guys,
My buddy just purchased a 2007 F550, generally in great shape, 120,000 miles but it has several issues, likely due in part, to having been parked for about a year prior to the auction. I'm mainly a 7.3 guy so the 6.0 has features I'm not 100% familiar with so I'd like your thoughts on the following:
1. Overboost/limp at highway speeds - Boost seems to run awfully high just cruising down the highway, on the order of 22 PSI, spiking to 30+ on uphill pulls. This is triggering a CEL and limp mode until the truck is shut down. To me, not knowing anything else, this sounds like the VGT is not adjusting for different load conditions, nozzle staying too far closed. Does this sound reasonable? Is it possible to clean the turbo or maybe the control unit is fried?
2. Ride is awful - This particular truck is the smallest, lightest F550 and it rides like it has no suspension. Is there a way to "de-rate" the suspension since the owner doesn't need the full load carrying capacity?
3. High RPM's at highway speed - I'm assuming this has 4.88 or some other similar gearing. What are the options for something more reasonable like 4.11? Is 3.73 too low? Replacement ring/pinion? OD unit?
4. Dash gauges/lighting sometimes flashes or goes does - Is this a known problem on these trucks?
Thanks as always for your input!
My buddy just purchased a 2007 F550, generally in great shape, 120,000 miles but it has several issues, likely due in part, to having been parked for about a year prior to the auction. I'm mainly a 7.3 guy so the 6.0 has features I'm not 100% familiar with so I'd like your thoughts on the following:
1. Overboost/limp at highway speeds - Boost seems to run awfully high just cruising down the highway, on the order of 22 PSI, spiking to 30+ on uphill pulls. This is triggering a CEL and limp mode until the truck is shut down. To me, not knowing anything else, this sounds like the VGT is not adjusting for different load conditions, nozzle staying too far closed. Does this sound reasonable? Is it possible to clean the turbo or maybe the control unit is fried?
2. Ride is awful - This particular truck is the smallest, lightest F550 and it rides like it has no suspension. Is there a way to "de-rate" the suspension since the owner doesn't need the full load carrying capacity?
3. High RPM's at highway speed - I'm assuming this has 4.88 or some other similar gearing. What are the options for something more reasonable like 4.11? Is 3.73 too low? Replacement ring/pinion? OD unit?
4. Dash gauges/lighting sometimes flashes or goes does - Is this a known problem on these trucks?
Thanks as always for your input!