There used to be a company called Clifford Research, that made parts for 6 cylinder inline motors, only. They can help with the 235. I will tell you this, too. The 235 in that year, put out a bit more HP, as an automatic, version, over the stick shift model. You may want to modify the suspension, as well. Art Morrison, in Washington state, has a specialty line for your rig, as well.
When you will be sustaining a speed of over 45 mph
Tires are out of balance ( maybe ) A bad u-joint in the driveshaft will cause it too. Check these things.
146 mph (235 km/h)
55 mph
1 mph = 1.609344 kph378/1.609344 = 235 mph
Several things could cause that: Worn shocks/struts Worn front end parts Tires out of balance Drive shaft out of balance Loose wheel
If you had 235 / 75 / 15 tires and switched to 235 / 60 / 15 tires : When your speedometer read 60 MPH you would actually be travelling at 54.2 MPH ( if that's what you are asking ? )
While I have not tried it in a 2007 Chevy Pickup yet, I have tried it in a 2006 2500 with a Duramax. (On a closed course with a professional driver, of course). It is limited to 100 mph. I have also driven many other Chevy trucks from 1999-2006, and they were all limited to 100 mph as well. Usually this is done by the manufacture based on tire speed rating.
You can but you should not. The 235/85-16 tire will be way too tall and will have a diameter that is 2.22" larger. This will cause your speedometer to be 4.2 mph too slow at 60 mph. This is not a good swap.
120 mph
About 4 hr 15 min.
3 hours 55 minutes at 60 mph