Elsewhere, some auto yield spreads extended the recent narrowing trend, boosted by stronger European equities and softening oil prices.
"We saw some out-performance from longer-dated autos as the oil price came down, but overall the market is doing better," said one trader. "Where people were short they are now getting back to neutral."
General Motors' 8.375 bond due in June 2033 was four to five basis points tighter at 1419 GMT at 275 basis points over Bunds, the trader said.
London Brent crude futures slipped more than a dollar on Thursday as fund profit taking and trade selling deepened a technical correction from last week's record highs. European stocks rose, though US equity indexes opened lower after a larger-than-expected rise in jobless claims.
The FTSE Euro Corporate Bond Index, which shows the average yield of investment-grade corporate bonds in euros over similarly dated government bonds, remained close to its all time lows, rising 0.3 basis point to 48.6 basis points.
The cost of credit protection on Britain's Hilton fell two basis points to 52.5 basis points, a trader said, after the hotel operator reported a 72 percent rise in first-half profit.
That means it costs 52,500 euros annually to insure 10 million euros of Hilton debt against default.
Hilton is starting to recover from the woes of 2003, when it suffered from the effects of the Iraq war, the Sars virus and global concern over terrorism.
Hilton operates around 400 hotels outside the United States and nearly 1,900 Ladbroke UK betting shops.
The company enjoyed strong trading at both those businesses, which drove earnings higher during the first six months.
Elsewhere, the cost of credit protection on French telecoms and media group Vivendi Universal fell three basis points to 66 basis points after the company said it had received permission to file under a new tax regime.
Vivendi said the change would result in tax savings of 500 million euros this year and total savings of 3.8 billion euros ($4.6 billion) over a longer horizon of up to seven years.
"The news is clearly beneficial for Vivendi's tax deduction effort," said Vladlen Andriouchtchenko, credit analyst at Commerzbank. "Vivendi spreads are already at tight levels but considering the current positive environment, and better-than-expected Q2 revenues, spreads are likely to remain well supported."
The cost of credit protection for "junk"-rated Ahold rose 10 basis points to around 212 basis points after the Dutch retailer reported disappointing second-quarter profits and announced the surprise resignation of its chairman.
Ahold said its second-quarter operating profit fell to 169 million euros ($204.3 million), well below 222 million euros posted for the same period last year and analysts' expectations of a profit of 258.5 million euros in a Reuters poll.