I have a 2003 H2 for over a year and purchased it with 37 inch tires on it an it drove great, shifted properly and had very good pickup from start.


I had a leak in my main rear seal, the dealer had to drop my trans to get to it to repair it. Since I got the truck back and I mean as I was leaving the dealership I noticed the truck did not respond like it used to before they touched it. When I had brought the truck to dealer, from the stop, the truck had good pickup, shifting into 2nd gear like around 2k rpms, now pressing gas pedal the same way, truck is slow from stop and doesn't shift til between 2500-3500 rpms. I thought it was my transmission so I brought it to someone I know who owns a gibralter and he drove it with me for an hour, had the scanner connected and said the trans is fine, no slipping, etc but he too felt the trans shifting very late into 2nd gear. Trans oil is fine, he even dropped the pan and inspected all parts and says everything is good. He says maybe its something with the computer in truck not knowing the size of the tires I have on truck. He said maybe when they disconnected battery and trans from truck for a period of time the computer lost its tune. I checked the speed of speedometer and speed on my iphone app and they are identical. He said there is more to it than just comparing the speed. Someone told me I would have to put on the stock tires, clear the computer settings, then change the tires back to my 37's. I don't know what to think or who to believe. I know others had a similar issue and had to rebuilt their but I find it very odd that this happened after I dropped the truck off at dealer and before I picked it up. I wonder if the tune got wiped after the dealer tried to download updates to computer. Has anyone experienced this before? Could getting a tune on truck since I have 37 inch tires fix this issue? Why is it only affecting getting into 2nd gear? Even though the transmission guy says its not slipping could it be that trans needs a rebuild? Its just odd that it happened while getting fixed at dealer.

 

I think the truck had a tune on it when I bought it in aug 14. The dealer must have wiped it out. I think this is the case cause this 03 was much quicker than my 05. Well next Wednesday I will put a tune omit and get 32 more HP and some more torque and see how it drives.